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NBER WORKING PAPER SERIES
DOES PRIVATE EQUITY INVESTMENT IN HEALTHCARE BENEFIT PATIENTS?
EVIDENCE FROM NURSING HOMES
Atul Gupta
Sabrina T. Howell
Constantine Yannelis
Abhinav Gupta
Working Paper 28474
http://www.nber.org/papers/w28474
NATIONAL BUREAU OF ECONOMIC RESEARCH
1050 Massachusetts Avenue
Cambridge, MA 02138
February 2021
We are grateful to Abby Alpert, Pierre Azoulay, Zack Cooper, Liran Einav, Matthew Grennan,
Arpit Gupta, Jarrad Harford, Steve Kaplan, Holger Mueller, Aviv Nevo, Adam Sacarny, Albert
Sheen, Arthur Robin Williams, and participants at the NBER Aging Summer Institute, American
Economics Association, UBC Winter Finance Conference, Whistler Junior Health Economics
Summit, Virtual Corporate Finance Seminar, ESSEC, Norwegian School of Economics,
Oklahoma Price, PE Research Consortium (PERC) Annual Symposium, Tulane, NYU Stern, U
Penn Wharton, Yale Health Policy, Oregon Lundquist, and Johns Hopkins Carey for their
comments and suggestions. Jun Wong, Mei-Lynn Hua, and Sarah Schutz provided excellent
research assistance. We thank Christianna Williams of Abt Associates for insights into CMS
quality measures, Liz Liberman for industry information, and Mohan Ramanujan at NBER for
assistance with the CMS data. Funding from the Wharton Dean’s Research Fund and the Mack
Institute (Gupta), the Kauffman Foundation (Howell), and the Fama Miller Center at the
University of Chicago (Yannelis) is greatly appreciated. We gratefully acknowledge funding
through National Institute of Aging pilot grant P01AG005842-31. All remaining errors are our
own. The views expressed herein are those of the authors and do not necessarily reflect the views
of the National Bureau of Economic Research.
NBER working papers are circulated for discussion and comment purposes. They have not been
peer-reviewed or been subject to the review by the NBER Board of Directors that accompanies
official NBER publications.
© 2021 by Atul Gupta, Sabrina T. Howell, Constantine Yannelis, and Abhinav Gupta. All rights
reserved. Short sections of text, not to exceed two paragraphs, may be quoted without explicit
permission provided that full credit, including © notice, is given to the source.Does Private Equity Investment in Healthcare Benefit Patients? Evidence from Nursing Homes
Atul Gupta, Sabrina T. Howell, Constantine Yannelis, and Abhinav Gupta
NBER Working Paper No. 28474
February 2021
JEL No. G3,G32,G34,G38,I1,I18
ABSTRACT
The past two decades have seen a rapid increase in Private Equity (PE) investment in healthcare,
a sector in which intensive government subsidy and market frictions could lead high-powered for-
profit incentives to be misaligned with the social goal of affordable, quality care. This paper
studies the effects of PE ownership on patient welfare at nursing homes. With administrative
patient-level data, we use a within-facility differences-in-differences design to address non-
random targeting of facilities. We use an instrumental variables strategy to control for the
selection of patients into nursing homes. Our estimates show that PE ownership increases the
short-term mortality of Medicare patients by 10%, implying 20,150 lives lost due to PE
ownership over our twelve-year sample period. This is accompanied by declines in other
measures of patient well-being, such as lower mobility, while taxpayer spending per patient
episode increases by 11%. We observe operational changes that help to explain these effects,
including declines in nursing staff and compliance with standards. Finally, we document a
systematic shift in operating costs post-acquisition toward non-patient care items such as
monitoring fees, interest, and lease payments.
Atul Gupta
Wharton Health Care Management
3641 Locust Walk, CPC 306
Philadelphia, PA 19104
atulgup@wharton.upenn.edu
Sabrina T. Howell
NYU Stern School of Business
KMC 9-93
44 West 4th Street
New York, NY 10012
and NBER
showell@stern.nyu.edu
Constantine Yannelis
Booth School of Business
University of Chicago
5807 S. Woodlawn Avenue
Chicago, IL 60637
and NBER
constantine.yannelis@chicagobooth.edu
Abhinav Gupta
New York University
agupta4@stern.nyu.edu1 Introduction
The U.S. spends more than other developed countries on healthcare, yet has worse health
outcomes (Garber and Skinner, 2008). In light of evidence from other sectors, private equity
(PE) ownership of healthcare providers could improve productivity (Kaplan, 1989; Davis
et al., 2014; Bloom et al., 2015b; Bernstein and Sheen, 2016). PE ownership can affect
firm performance because it confers distinct incentives to quickly and substantially increase
firm value.1 However, PE’s success in other sectors may not be relevant to healthcare,
which suffers from unique market frictions. For example, patients cannot accurately assess
provider quality, they typically do not pay for services directly, and a web of government
agencies act as both payers and regulators (Cutler, 2011; Skinner, 2011). These features
weaken the natural ability of a market to align firm incentives with consumer welfare and
could mean that high-powered incentives to maximize profits have detrimental implications
for consumer welfare (Hansmann, 1980; Hart et al., 1997; Chandra et al., 2016).
Policymakers appear increasingly concerned about this possibility given the rapid
growth of PE in healthcare. For example, in 2019 U.S. Senators asked about “the role of
PE firms in the nursing home care industry, and the extent to which these firms’ emphasis
on profits and short-term return is responsible for declines in quality of care," while a
member of the British Parliament argued that PE-owned nursing homes in the UK pursue
"profiteering, cost and corner cutting, all the while their owners are loading them up on
debt with high interest rates and expecting the taxpayer to pay when it fails" (Brown et al.,
2019; Hodgson, 2020).2 Meanwhile, voices from the private sector often paint a different
picture; for example, a 2019 report from consulting firm EY concluded that “Not only is
PE perceived to have a beneficial overall impact on health care businesses, it is also
considered to positively influence the focus on quality and clinical services" (Saenz, 2019).
This debate has come to the fore in part because of rising PE activity in U.S. healthcare
1See Section 2.2 for an explanation of PE and its incentive structure.
2Policymaker concern has focused not only on nursing home quality (Doggett et al., 2020), but also surprise
medical bills (Cooper et al., 2020) and predatory acquisitions of physician practices (King, 2020), among other
areas. Also see Flood (2019) and Lewis (2019).
1over the last two decades, with total investment increasing from less than $5 billion in 2000
to more than $100 billion in 2018 (Appelbaum and Batt, 2020). PE-owned firms provide the
staffing for more than one-third of emergency rooms, own large hospital and nursing home
chains, and are rapidly expanding ownership of physician practices.3 Thus far, evidence to
inform the animated policy discussion is limited and inconclusive.
We focus on nursing homes in the U.S., which represent a large sector with spending at
$166 billion in 2017 projected to grow to $240 billion by 2025 (Martin et al., 2018).
Nursing homes offer an attractive setting in which to examine the impact of PE in
healthcare. First, they have historically had a high rate of for-profit ownership (about 70%),
allowing us to study the effects of PE ownership relative to for-profit ownership more
generally. Second, PE firms have acquired both large chains and independent facilities,
enabling us to make progress in isolating the effects of PE ownership from the related
phenomenon of corporatization in medical care (Eliason et al., 2020). We use patient- and
facility-level administrative data from the Centers for Medicare & Medicaid Services
(CMS), which we match to PE deal data. The data include 18,485 unique nursing homes
between 2000 and 2017. Of these, 1,674 were acquired by PE firms in 128 unique deals.
We observe about 7.4 million unique Medicare patients.
We overcome two empirical challenges to estimating causal effects of PE ownership.
The first is non-random selection of acquisition targets. To address this we include facility
fixed effects, which also eliminate cross-sectional differences in the types of locations where
PE firms tend to buy nursing homes. The second challenge is unobserved changes in patient
composition following PE ownership, perhaps reflecting new advertising, hospital ties, or
patient reactions to quality. We control for the patient-facility match with a differential
distance instrumental variables (IV) strategy (McClellan et al., 1994; Grabowski et al., 2013;
Card et al., 2019), exploiting patient preference for a nursing facility close to their home (the
median distance is 4.6 miles). To our knowledge, no national study on PE or on ownership
in healthcare has simultaneously addressed both challenges.
A key measure of patient welfare is short-term survival. We find that going to a PE-
3See Bruch et al. (2020); Brown et al. (2020); Casalino (2020).
2owned nursing home increases the probability of death during the stay and the following
90 days by 1.7 percentage points, about 10% of the mean. This estimate implies about
20,150 Medicare lives lost due to PE ownership of nursing homes during our sample period.
We use the observed age and gender distribution of Medicare decedents to estimate the
corresponding implied loss in life-years – 160,000. Using a conventional value of a life-
year from the literature, this estimate implies a mortality cost of about $21 billion in 2016
dollars. To put this in perspective, this is about twice the total payments made by Medicare
to PE facilities during our sample period, about $ 9 billion.
The mortality effect is concentrated among older patients, especially those with
relatively low disease burdens. Exploring treatment effect heterogeneity more formally
using Marginal Treatment Effect (MTE) analysis, we find evidence of reverse selection on
treatment gains, i.e., patients with the lowest unobserved resistance to going to a PE-owned
facility experience the highest increase in mortality (nearly 4 pp). We estimate an
unconditional Average Treatment Effect (ATE) of about 1.3 pp. Hence, the conclusion that
patients are worse off at PE-owned facilities can be generalized beyond compliers to the
average Medicare patient. However, we also estimate negative MTE values for patients
with the highest unobserved resistance, implying that a small fraction of patients are better
off receiving care at such facilities.
The effect on mortality is robust to a battery of specification checks, and does not
appear in a placebo analysis testing for pre-buyout effects. It also remains intact when we
restrict our attention to PE acquisitions of the largest chains, in which chain size remained
constant over the sample period, implying that the effect reflects the nature of ownership
rather than consolidation or corporatization more broadly. To ensure the effect is not
spurious, we study other measures of patient well-being using the same IV approach. We
find that going to a PE-owned nursing home increases the probability of taking
antipsychotic medications – discouraged in the elderly due to their association with greater
mortality – by 50%. Similarly, patient mobility declines and pain intensity increases
post-acquisition. Finally, the amount billed per 90-day episode increases by 11%. Taken
together, these results suggest that PE ownership decreases nursing home productivity, as
3measured by our proxies for quality output per dollar spent.
To explore mechanisms for the effect on mortality, we assess operational changes using
facility-level data. Here we are limited to using a differences-in-differences research design,
which has been standard in the literature on PE effects. We find negative effects on facility
Five Star ratings, which are constructed by CMS to provide summary information on quality
of care. We next consider nurse availability, which is the most important determinant of
quality of care (Zhang and Grabowski, 2004; Lin, 2014). We find that PE ownership leads
to a 3% decline in hours per patient-day supplied by the frontline nursing assistants who
provide the vast majority of caregiving hours and perform crucial well-being services such
as mobility assistance, personal interaction, and cleaning to minimize infection risk and
ensure sanitary conditions. Overall staffing declines by 1.4%.
The loss of front-line staff is most problematic for older but relatively less sick patients,
who drive the mortality result. There may be less scope to reduce the costs of care for
the sicker patients, as they have explicit medical needs. Elevated antipsychotic use could
also be partly explained as a substitution response to lower nurse availability (Cawley et
al., 2006). We can explain about a third of the mortality effect using previously published
mortality effects of antipsychotics and lower nurse availability and assuming these factors
are additive (Schneider et al., 2005; Tong, 2011). However, this may be an understatement
if these factors are more harmful when they interact.
Finally, we assess facility finances to shed light on how the financial strategies particular
to the PE industry affect operations. A puzzle is why nursing homes are attractive targets
given their low and regulated profit margins, often cited at just 1-2%. Using CMS cost
reports, we find that there is no effect of buyouts on net income, raising the question of how
PE firms create value. There are three types of expenditures that are particularly associated
with PE profits and tax strategies: “monitoring fees" charged to portfolio companies, lease
payments after real estate is sold to generate cash flows, and interest payments reflecting the
importance of leverage in the PE business model (Metrick and Yasuda, 2010; Phalippou et
al., 2018). We find that all three types of expenditures increase after buyouts, with interest
payments rising by over 300%. These results, along with the decline in nurse availability,
4suggest a systematic shift in operating costs away from patient care.
This paper contributes to three strands of the literature. First, we provide new evidence
on the effects of PE ownership on target firm operations (Boucly et al., 2011), product quality
(Lerner et al., 2011; Fracassi et al., 2020), and value (Gupta and Van Nieuwerburgh, 2019;
Bernstein et al., 2019; Biesinger et al., 2020). We overcome most limitations of previous
studies on PE in healthcare, such as limited geographies, a short sample period, a lack of
patient-level data, or a small number of deals (Stevenson and Grabowski, 2008; Harrington
et al., 2012; Pradhan et al., 2013, 2014; Cadigan et al., 2015; Huang and Bowblis, 2019;
Gondi and Song, 2019; Casalino, 2020; Gandhi et al., 2020).
In contrast with much of the existing literature, and likely reflecting the considerable
market frictions in healthcare, our results suggest that PE owners may breach implicit
contracts with stakeholders to maximize profits (Shleifer and Summers, 1988). Eaton et al.
(2019) come to the same conclusion in their study of PE ownership of colleges. It is
noteworthy that nursing homes operate under much more intense regulatory scrutiny of
their daily operations than do colleges. Hence, our results raise concerns about the
effectiveness of the elaborate state and federal oversight infrastructure in place to ensure
nursing home quality.
Second, this paper adds to the literature on how provider ownership interacts with price
incentives and regulation in healthcare Duggan (2000); Grabowski and Hirth (2003);
Grabowski et al. (2013); Clemens and Gottlieb (2014); Adelino et al. (2015); Hill et al.
(2019); Curto et al. (2019).4 Some work points to non-pecuniary objectives of nonprofits as
one reason nonprofit providers can outperform for-profits. Our results appear consistent
with this theme, potentially raising questions about whether antitrust regulators should
prospectively review PE deals in healthcare. While the large deals in our sample did not
soften competition, they may have hurt consumers.5
4There is also a related literature on competition in healthcare markets Bloom et al. (2015a), Curto et al.
(2021); Grabowski and Hirth (2003); Dafny et al. (2012); Cooper et al. (2018); Pelech (2018); Ho and Lee
(2019).
5The largest deals in our sample involved purchases of nursing home chains owning hundreds
of facilities already and which remained stable in size. Both the US House and Senate are
considering expanding the scope of the prevailing anti-trust laws. As example, see https:
//www.cnbc.com/2021/02/04/klobuchar-unveils-sweeping-antitrust-bill-laying-out-
5Third, this paper contributes to the emerging literature on the industrial organization
of the nursing home sector, which has received less attention than hospitals in economics
(Lin, 2015; Hackmann and Pohl, 2018; Hackmann, 2019). Previous work has focused on
the role of competition and payment rates in determining quality. Our results imply that
owner incentives are of first-order importance, which may be helpful for policymakers as
they consider regulatory actions to improve transparency and accountability. For example,
in light of prior work showing how PE increases performance when incentives between
investors and consumers are well-aligned, government reimbursements targeting outcomes
could potentially improve patient welfare. These issues have become more urgent as the
COVID-19 pandemic has exposed flaws in the regulation and financing of long-term care
facilities, which have accounted for nearly 40% of U.S. deaths from the virus.6
The paper proceeds as follows. Section 2 provides institutional background. Section 3
describes the data. The strategy for patient-level analysis is explained in Section 4, and the
results are in Section 5. The facility-level estimation is in Section 6. Section 7 concludes.
2 Institutional Background
2.1 The Economics of Nursing Homes
Nursing homes provide both short-term rehabilitative stays – usually following a hospital
procedure – as well as long-term custodial stays for patients unable to live independently.
There are two unique features of the long-term care market in the U.S. relative to other
healthcare subsectors. First, government payers (Medicaid and Medicare) account for 75%
of revenue, while private insurance plays a much larger role in other subsectors (Johnson,
2016).7 Second, about 70% of nursing homes are for-profit, which is a much larger share
than other subsectors. For example, fewer than one-third of hospitals are for-profit.
her-vision-as-new-subcommittee-chair-.html.
6Source: The New York Times Coronavirus Tracker, as of October 2020.
7Medicaid is a means-tested insurance program targeted at low income and disabled non-elderly
individuals. It is the primary payer for custodial care and accounts for about 60% of nursing home patient-
days in our data. Medicare is an entitlement health insurance program for individuals older than age 65, and it
covers limited short-term rehab care following hospital inpatient care, accounting for 15% of patient-days.
6Policymakers have long been concerned about low-quality care at nursing homes in the
U.S. and for-profit ownership has often been proposed as a causal factor (Institute of
Medicine, 1986; Grabowski et al., 2013).8
As with any business, the economics of nursing homes are shaped by the nature of
demand, the cost structure, and the regulatory environment. On the demand side, nursing
homes serve elderly patients but are paid by third-party, largely government payers. Over
95% of facilities treat both Medicare and Medicaid patients (Harrington et al., 2018). Both
programs pay a prospectively set amount per day of care for each covered patient (‘per
diem’), which does not incorporate quality of care, reputation, or other determinants that
would be considered by a well-functioning market. These rates are non-negotiable, and
facilities simply choose whether they will accept beneficiaries of these programs. Medicare
fee-for-service pays much more, at roughly $515 per patient day relative to $209 per patient
day from Medicaid.9 Overall profit margins are in the low single digits (MedPAC, 2017),
a topic we return to at the end of the paper. Payments are adjusted for patient complexity,
so there is an incentive to overstate their severity—a practice known as ‘up-coding.’ This
makes it difficult to use risk as an outcome.
Nursing homes provide institutional care and so have high fixed costs, making the
occupancy rate an important driver of profitability. Nursing staff represent the largest
component of operating cost, at about 50% (Dummit, 2002). Broadly speaking, there are
three types of nurses. Low-skill Certified Nurse Assistants (CNAs) account for about 60%
of total staff hours and provide most of the direct patient care. Licensed Practical Nurses
(LPNs) have more training and experience than CNAs but cannot manage patients
independently. Registered Nurses (RNs) have the highest skill and experience levels, and
can independently determine care plans for patients. LPNs and RNs each account for about
8This concern is frequently reflected in the popular media, including as a reason for high death rates
from Covid-19 in nursing homes. For example, a New York Times article in December, 2020 asserted that:
“Long-term care continues to be understaffed, poorly regulated and vulnerable to predation by for-profit
conglomerates and private-equity firms. The nursing aides who provide the bulk of bedside assistance still
earn poverty wages, and lockdown policies have forced patients into dangerous solitude" (Kim, 2020).
9https://skillednursingnews.com/2019/03/medicare-advantage-eats-into-margin-
gains-for-skilled-nursing-facilities/. Medicaid still pays more than the marginal cost of
treatment per day. Hackmann (2019) calculates that the marginal cost of treatment per-day is about $160 on
average.
720% of nurse hours. Nurse availability is crucial to the quality of care and there is a
consensus that low ratios of nursing staff to residents are associated with higher patient
mortality and other adverse clinical outcomes (Tong, 2011; Lin, 2014). Staffing ratios are
therefore standard metrics to examine nursing home quality (Hackmann, 2019).
Economists have long emphasized the importance of information asymmetry between
patients and healthcare providers (McGuire, 2000). It is difficult for patients to assess
nursing home quality and compare it to available alternatives, and as discussed above, price
is not a helpful quality signal in this setting. Reputation is therefore likely to have an
unusually large influence on demand for nursing homes (Arrow, 1963). Profit maximizing
facilities should optimally invest in building and sustaining their reputation. This creates a
dynamic incentive problem where they could generate higher profits in the short-term by
cutting patient care costs (nursing staff, for example), but they may optimally sacrifice
these short-term profits in order to maintain their reputation and safeguard patient demand
for the long-term. It remains unclear which factor inputs affect nursing home reputation,
but evidence from prior studies suggests that patient demand does not respond to poor
quality scores on government mandated report cards (Grabowski and Town, 2011; Werner
et al., 2012).
2.2 The Economics of Private Equity Control
PE firms conduct leveraged buyouts (LBOs), in which a target firm is acquired primarily
with debt financing – which is placed on the target firm’s balance sheet – and a small
portion of equity.10 PE is associated with particularly high-powered incentives to maximize
profits because fund managers are compensated through a call option-like share of the
profits, employ large amounts of leverage collateralized with target firm assets, aim to
liquidate investments within a short time frame, and do not have existing relationships with
target firm stakeholders (Kaplan and Stromberg, 2009). Specifically, the compensation of
the General Partners (GPs) who manage PE funds stems primarily from increasing
10Kaplan and Stromberg (2009) provide a detailed discussion of the PE business model and review the
academic evidence on their effects. In the interest of brevity, we limit our discussion.
8portfolio company value between the time of the buyout and an exit, when the company is
sold to another firm or taken public. GPs typically receive 20% of profits after a hurdle
rate, which the fund’s investors (Limited Partners) are guaranteed before GPs receive any
profits. GPs also receive transaction and monitoring fees, which are not tied to
performance. Overall, however, PE managers typically do not earn returns if the business
continues as-is, motivating aggressive value-creation strategies. In contrast, a traditional
business owner running the firm as a long-term going concern with a lower debt burden
may prefer lower but more stable profits.
A large literature in finance beginning with Kaplan (1989) and Kaplan and Schoar
(2005) has shown that in part due to the call option-like nature of GP compensation, PE
buyouts increase productivity, operational efficiency, and generate higher returns. Kaplan
and Stromberg (2009) argue that PE owners increase firm value through three channels,
which they call financial, governance, and operations engineering. The first channel
includes the alleviation of credit constraints (Boucly et al., 2011), which may lead to
increases in investment and improved operations, and exploiting the favorable tax code
treatment of debt financing (Spaenjers and Steiner, 2020), which may increase financial
stress and the chances of default.
Governance engineering includes a number of changes to the compensation, benefits,
and composition of the management team at the target firm to align their incentives with
those of the PE owners. For example, in addition to frequently changing key managers, PE
owners also increase the equity stake of the management team and introduce performance-
based compensation (Gompers et al., 2016). Bloom et al. (2015b) show that PE-owned firms
are better managed than similar firms that are not PE-owned.
Operations engineering refers to the more recent practice of PE firms applying their
industry expertise to add value to their investments. PE owners identify both strategic and
operational opportunities, such as re-branding, organization restructuring, investing in new
technology, expanding to new markets, and cost-cutting (Gadiesh and MacArthur, 2008;
Acharya et al., 2013; Bernstein and Sheen, 2016). Davis et al. (2014) show that PE buyouts
are linked to greater labor churn, the expansion of efficient operations and the closure of
9inefficient operations.
Considering these changes in the context of nursing homes, the effects on patients are
theoretically ambiguous. On the one hand, better management, stronger incentives, and
access to credit may lead to improvements in care quality. On the other hand, three forces
could adversely affect quality. The first is that cost cutting measures and a focus on capturing
subsidies could come at the expense of quality improvement efforts. The second is that
the nursing home incurs a large debt obligation as part of the buyout, and the resulting
interest payments can reduce the cash available for care. A related additional cost is leasing
property that formerly was owned by the nursing home. PE owners often sell real estate
assets shortly after the buyout, which generates cash that can be returned to investors. Such
cash flows early in the deal’s lifecycle boost ultimate discounted returns. For example, in
one of the largest PE deals in our sample, the Carlyle Group bought HCR Manorcare for
about $6.3 billion in 2007, of which roughly one quarter was equity and three-quarters were
debt. Four years later, Carlyle sold the real estate assets for $6.1 billion, offering investors
a substantial return on equity (Keating and Whoriskey, 2018). Afterward, HCR Manorcare
rented its facilities; the monthly lease payments are essentially another debt obligation, and
a Washington Post investigation found that quality of care deteriorated following the real
estate sale (Keating and Whoriskey, 2018).
Finally, the third force is the relatively short-term time horizon of PE investments,
which could push managers to focus on maximizing short-term profits even if they come at
the expense of long term reputation and performance. In the case of HCR Manorcare, the
nursing home chain was ultimately unable to make its interest and lease payments and
entered bankruptcy proceedings in the spring of 2018. Carlyle sold its stake to the landlord.
3 Data and Descriptive Statistics
In this section we briefly summarize our data sources and provide descriptives about the
sample, including an analysis of PE targeting. In Appendix A, we describe these elements
in comprehensive detail.
103.1 Data
We obtained facility-level annual data between 2000 and 2017 from publicly-available
CMS sources. In each year we observe about 15,000 unique skilled nursing facilities (we
use the term “nursing home" interchangeably), for a total of approximately 280,000
observations. These data include variables such as patient volume, nurse availability, and
various components of the Five Star ratings. The ratings first appear in 2009. Fortunately,
half of the PE deals in our sample occurred after 2009.
Our second data source consists of patient-level data for Medicare beneficiaries from
2004 to 2016. We use the Medicare enrollment and claims files (hospital inpatient,
outpatient, and nursing homes) for the universe of fee-for-service Medicare beneficiaries.
We merge these files with detailed patient assessments recorded in the Minimum Data Set
(MDS) to obtain additional clinical insights. These data are confidential and were accessed
under a data use agreement with CMS. They include patient enrollment details,
demographics, mortality, and information about care in nursing homes and hospitals during
this period.
In patient-level analysis, the unit of observation is a nursing home stay for a Medicare
beneficiary that begins during our sample period, which we begin in 2005 in order to have
at least one look-back year. We consider only the patient’s first nursing home stay in our
entire sample period so that we can unambiguously attribute outcomes to one facility and
make our patient sample more homogeneous. This produces a sample of more than seven
million patients over 12 years. We are most interested in the effect on mortality, which is an
unambiguously bad outcome, has little measurement error, and is difficult to “game” on the
part of a facility or a government agency. For these and other reasons, short-term mortality
(with suitable risk adjustment) has become the gold-standard measure of provider quality
in the health economics and policy literature (McClellan and Staiger, 1999). We use an
indicator for death during the stay or within 90 days following discharge, based on death
dates recorded in the Medicare master beneficiary summary file. There is a high level of
short-term mortality—one in six patients die within three months of discharge—indicating
11the general morbidity of this patient cohort.
We use two measures of spending: the amount billed to Medicare for the patient stay,
and the amount for the stay plus the following 90 days, in case better quality care leads to
lower subsequent spending (both in 2016 dollars). Medicare covers the entire cost until the
21st day of stay, at which point the patient begins paying a coinsurance. Consequently, about
90% of total payments in our data are made by Medicare and patients bear the remainder.
We complement the mortality analysis by examining some ancillary measures of patient
well-being using the clinical assessments. We study four outcomes that CMS uses when
computing the Five Star quality ratings for nursing homes. The first is an indicator for the
patient starting antipsychotic medication during the stay. Antipsychotic use in the elderly
is known to increase mortality, and non-pharmaceutical interventions such as music and
breathing exercises have been shown to be more effective (Taragano et al., 1997; Kuehn,
2005; Sink et al., 2005; Schneider et al., 2005; Banerjee et al., 2011; Press and Alexander,
2013). The second is an indicator for the patient’s self-reported mobility score declining
during the stay. The third is an indicator for developing a pressure ulcer. The fourth is an
indicator for the patient’s self-reported pain intensity score increasing during the stay.
To identify nursing homes acquired in PE deals, we make use of a proprietary list of
transactions in the “elder and disabled care” sector compiled by Pitchbook Inc., a leading
market intelligence firm in this space. The deals span 2004 to 2015, so that we will have
sufficient time to evaluate outcomes. We match the target names to individual nursing
facilities using name (facility or corporate owner) and address as recorded in the CMS data.
This process yields 128 deals, which correspond to a change in ownership to PE for 1,674
facilities. The vast majority of deals in Pitchbook are not at hazard of matching, as they
concern assisted living or other elder care companies that are not Medicare-accepting
skilled nursing facilities. (See Appendix A for details.)
Figure B.1 shows the number of deals in each year; the deals are spread over time, and
no part of the business cycle dominates. The deals are also spread across PE firms. In
total, our data contain 136 unique PE firms that acquired nursing homes. Most deals are
syndicated and involve multiple PE firms. Table B.1 presents the top 10 deals by number
12of facilities acquired. On average, we observe PE-owned facilities for eight years post-
acquisition. Hence the results should be interpreted as medium to long-term effects of PE
ownership. It is difficult to ascertain whether we comprehensively capture PE activity in
this sector. While there is no ‘official’ tally of PE-owned nursing homes to benchmark
against, our sample size compares favorably against an estimate of 1,876 nursing homes
reportedly acquired by PE firms over a similar duration, 1998–2008 (GAO, 2010). The PE
investors in our sample include very large funds, smaller funds, and specialized healthcare
PE investment funds. The funds which account for the greatest number of deals are Onex,
Fillmore Capital Partners, The Hillview Group, The Carlyle Group, Cammeby International,
Heritage Partners, Lydian Capital, Formation Capital, and Oaktree.
3.2 Descriptive Statistics
Overall, PE investment in healthcare has increased dramatically in recent decades, as shown
using Pitchbook data in Panel A of Figure 1. Panel B focuses on the Elder and Disabled
Care sub-sector, which includes the nursing homes that we study as well as assisted living
and other types of care. The shaded areas in the graphs correspond to years after our sample
ends, and indicate that deal activity continued to accelerate beyond 2015. The bottom two
panels describe the skilled nursing facilities in our CMS data that are PE-owned. As of 2015,
PE-owned facilities represented about 9% of all nursing facilities in the data, corresponding
to an annual flow of about 100,000 patients. Note that the large spike in the mid-2000s seen
in all the graphs reflects an economy-wide PE boom during this period, and is not specific
to healthcare. Similarly, the flat lining in Panels C and D starting in 2010 reflects the lull in
deal activity due to the Great Recession. Given the patterns in Panel B, the share of facilities
that are PE-owned is likely substantially higher today.
Table 1 Panel A presents summary statistics on key variables used in the analysis at the
facility-year level, where a facility is a single nursing home. Panel B presents summary
statistics at the unique patient level on the final Medicare patient sample (recall we focus
on a patient’s first stay). PE targets are slightly larger, have fewer staff hours per resident,
13and a lower Overall Five Star rating. At the sector level, ratings and staffing have secularly
increased over time. For staffing, this reflects more stringent standards from regulators over
time. As the PE deals occurred primarily later in the sample, it is therefore remarkable that
they have lower measures of quality on average. Panel B shows that demographic measures
are similar across the types of facilities, such as patient age and a high-risk indicator.11
PE-owned facilities bill about 10% more per stay than non-PE facilities.
We describe which characteristics are associated with buyouts in Table A.1. Facilities
in more urban counties and in states with higher elderly population shares are more likely
to be targeted.12 County-level income, race, and home ownership do not predict buyouts.
Chain-owned facilities are more likely to be acquired than independent facilities, likely
reflecting the fixed costs of a PE deal. A higher share of Medicare patients (the omitted
group) is positively associated with being targeted. Finally, the Five Star overall rating has
a negative relationship with buyouts, indicating that PE firms target relatively
low-performing nursing homes. These factors remain statistically significant predictors
when included simultaneously in the same model, shown in column 5. These results
highlight the need to estimate the effects of PE ownership within-facility.
4 Empirical Strategy for Patient-Level Analysis
There are two primary concerns related to measuring the causal effects of PE ownership on
patient-level outcomes. First, PE funds may target facilities that are different in ways the
econometrician cannot observe. To address this concern, we include facility fixed effects,
eliminating time invariant differences across facilities. Second, following a PE buyout, the
composition of patients may change, confounding the analysis. Differential customer
selection following PE ownership could reflect both supply-side channels such as changes
in advertising and hospital referrals, or patient perceptions about PE ownership.
11We use the Charlson Comorbidity Index, a standard measure of patient mortality risk based on co-
morbidities. We create a high-risk indicator that is equal to one if the previous-year Charlson score is greater
than two.
12The map in Figure B.2 shows that deals are not excessively concentrated in particular areas of the country.
14Recent studies have documented that nursing homes can select patients based on patient
characteristics, only some of which are observable to CMS (Hackmann and Pohl, 2018;
Gandhi, 2020). We see evidence of changes in patient risk following PE ownership in our
data. Table B.5 Panel A presents point estimates from differences-in-differences models
that exploit variation in the timing of the PE deals across facilities. We test for changes in
patient risk (assessed at the time of admission) following acquisition. We examine effects
on a mix of acute and chronic conditions to broadly capture changes in patient risk. The
coefficients indicate that patients are less likely to suffer from Dementia and Alzheimers or
from acute conditions like Hip Fractures at the time of admission. However, they are also
more likely to have a Urinary Tract Infection (UTI). Figure B.3 presents the corresponding
event study plots, which generally suggest flat or declining trends in patient risk around the
time of the acquisition. We are concerned that if there is a similar decline in unobserved
patient risk following PE ownership, it will bias downward mortality and spending effects
obtained via OLS. Therefore, we develop an instrument for the match between patients and
nursing homes.
4.1 Distance Instrument
We use a differential distance instrument (McClellan et al., 1994) to control for endogenous
patient selection into nursing homes. The instrument exploits the well-known patient
preference for nearby healthcare providers (Einav et al., 2016; Card et al., 2019; Currie and
Slusky, 2020). This is especially true for nursing homes; for example, Hackmann (2019)
finds that the median distance between a senior’s residence and her nursing home is under
4.3 miles. This is also evident in our data—the median and 90th percentile distances
between a patient and her nursing home are 4.6 and 18 miles, respectively. About 35% of
all patients choose the facility located closest to them (see Figure B.4).13 As a result of
these patterns, this instrument has been useful in the nursing home setting to control for
patient selection (Grabowski et al., 2013; Huang and Bowblis, 2019).
13Distance patterns remain remarkably stable over time in our sample. Mean distance to facility is unaffected
by PE buyout, as shown in Figure B.4D.
15We compute the difference (in miles) between two distances: from a patient’s home
zip code to the closest PE-owned facility zip code; and from the patient’s residence to the
nearest non-PE facility zip code. A positive value indicates the patient is closer to a non-PE
facility. A lower differential distance value implies the nearest PE-owned facility is closer
to the patient. PE ownership evolves over time as more deals take place (and some PE funds
exit their investments), creating variation across years in differential distance for individuals
residing in the same zip code. Following convention in the literature, we drop patients with
outlier differential distance values.14
The first stage is estimated using Equation (1), and the second stage is estimated using
Equation (2). The endogenous regressor of interest PEi,j,r,t is an indicator set to one if patient
i in Hospital Referral Region (HRR) r chooses PE-owned facility j in year t. We instrument
with linear and squared differential distance, Di applicable to patient i based on her zip code,
z, and when the nursing home stay began.
PEi,j,r,t = αj + αr,t + ζ1Di + ζ2D2
i + X′
i,z ξ+ νi,j,r,t (1)
Yi,j,r,t = αj + αr,t + φPEi,j,r,t + X′
i,z γ+ εi,j,r,t (2)
Our preferred model controls for facility, αj, and patient HRR by year fixed effects, αr,t. The
vector Xi,z denotes patient risk controls including age, indicators for gender, marital status,
dual eligible, and 17 disease categories.15 We conduct multiple robustness checks, which
include adding time-varying socioeconomic variables at the patient’s zipcode-year level and
omitting all controls.16 Standard errors are clustered by facility to account for unobserved
correlation in outcomes across patients treated at the same nursing home.
The instrument is strongly predictive of choice of nursing home type. The first stage
results are reported in Table 2. Column 2 presents the estimates from our preferred
14Specifically, we drop patients with a differential distance value beyond 70 miles, which is approximately
the 95th percentile (i.e., the nearest PE facility is 70 miles further than the nearest non-PE facility). The
concern here is that these patients are plausibly located in a different market which PE facilities do not operate
in, and hence could differ in unobserved ways correlated with health or spending outcomes. To be symmetric,
we also drop (the very few) patients who have a differential distance value below -70.
15To construct these indicators, we use diagnoses codes recorded in claims billed over the three months prior
to the index nursing home stay (hospital stays, ED visits, and outpatient visits).
16The socioeconomic variables, from the American Community Survey, are annual median household
income, the share of the population that are white, that are renters rather than home-owners, and that are
below the Federal poverty line.
16specification. A five mile decrease in differential distance (0.3 s.d.) increases the
probability of going to a PE-owned nursing home by 2.3 percentage points (pp), a quarter
of the mean level. The F-statistic exceeds 200, well above conventional rule-of-thumb
thresholds for weak instruments.
4.2 Instrument Assumptions and Validation Tests
IV estimation differs from randomized controlled trials because the randomization of
patients to treatment is indirect rather than deliberate. As in all such analyses, we must rely
on two untestable identification assumptions. The first is conditional random assignment,
which requires that after conditioning on covariates, unobserved characteristics correlated
with the outcomes of interest are not correlated with differential distance. This assumption
subsumes the exclusion restriction, that the instrument affects outcomes only through its
effect on the patient’s probability of going to a PE facility. The second assumption is
monotonicity, which assumes that a decrease in differential distance makes all patients
more likely to choose a PE-owned facility. This is true on average, but the assumption is at
the patient-level which is untestable. Monotonicity is necessary to interpret the IV estimate
as a well-defined local average treatment effect (LATE).
An important test for randomization examines whether differential distance is
correlated with covariates, particularly those which may affect health outcomes, such as
risk. Comparing the estimates reported in columns 1 and 2 of Table 2, the coefficients on
differential distance are nearly unaffected by including patient-level controls, consistent
with random assignment. Figure 2 Panel A visually presents the relationship between
patient risk and the instrument and indicates little or no correlation.17
Additional evidence for random assignment is that patient characteristics are similar for
high and low values of differential distance. We document this in Table 3, where we
summarize 21 patient characteristics for above- and below-median differential distance
17We project the high-risk indicator (see Section A.2) on the controls we use in our main regression, and
collapse the residuals into twenty bins. Similarly, we run a regression of differential distance on the controls
and collapse the residuals into twenty bins. We plot the means of each bin, with the risk residuals on the Y-axis
and distance residuals on the X-axis. The figure also presents a fitted line and the slope coefficient.
17values. The top two rows of the table show that, consistent with a strong instrument,
below-median differential distance average is 2.7 miles, while the above-median average is
27 miles. The associated probability of going to a PE-owned facility declines from 17% to
2%. The patient characteristics in the subsequent rows are extremely similar across the two
groups. For example, 64% of each group are women, and about a quarter of the patients in
both groups have diabetes. While differential distance is highly predictive of going to a
PE-owned facility, it appears to randomize patients with respect to observed covariates.
PE funds may strategically target nursing homes located in places with certain desired
demographic and risk profiles. We account for stable differences in the patient catchment
of facilities by including facility fixed effects. However, it is possible that PE firms
strategically target geographic markets with desirable trends, for example with increasing
household income. To address this concern, we show robustness to including time-varying
zip code-level socioeconomic controls. We document that these controls do not affect the
first stage in Column 3 of Table 2. The use of HRR-specific year fixed effects further
mitigates the possibility of differential market trends biasing the effects.
A related concern may be that HRRs are too large and do not sufficiently control for
unobserved heterogeneity in trends across markets. Hence, we also test robustness to using
the more granular market definition of Health Service Areas (HSA) and counties.18 There
are nearly 800 HSAs and 3,000 counties, respectively, while there are only about 300 HRRs.
Columns 4 and 5 of Table 2 present results using these finer market definitions, respectively,
with slightly smaller estimates.
We provide evidence consistent with the monotonicity assumption in Figure 2 Panel B,
which contains a binscatter plot of the first stage, showing that the likelihood of going to a
PE-owned facility increases nearly linearly with differential distance. It is estimated in the
same way as Panel A described above, except that the outcome is an indicator for the facility
being PE-owned. The monotonicity assumption also implies that the first stage should be
18HSAs were developed by the National Center for Health Statistics of the Centers for Disease Control
in the mid 1990s. They are designed to identify a single county or contiguous sets of counties where
Medicare patients seek hospital care within the area. We use a slightly modified version developed by the
SEER program of the National Cancer Institute, available for download at https://seer.cancer.gov/
seerstat/variables/countyattribs/hsa.html.
18negative when estimated on sub-samples of patients with different characteristics. Table B.2
shows that when we estimate the relationship between below-median differential distance
and PE ownership (a simplified first stage), we recover coefficients that are very similar to
the full-sample result and all are significant at the .01 level for a variety of sample splits by
age, gender, race, and zipcode income level.
Table B.2 also helps characterize compliers relative to the average patient at a PE
facility. The ratio of the first stage coefficient for a subsample with a specific attribute to
that obtained for the full sample provides the likelihood of compliers having that particular
attribute relative to the average PE patient.19 Compliers appear to have a very similar age
distribution and the probability of being male, married, or white. Intuitively, distance-based
compliers are more likely to be from a low-income zipcode.
5 Patient-Level Effects
This section presents the main results of the paper. We focus on the effects of PE ownership
on short-term mortality and spending per patient, discussing the LATE, heterogeneity in
treatment effects, as well as tests for the mechanism and robustness.
5.1 Main Effects on Mortality and Spending
Table 4 presents the results obtained by estimating Equation (2). These models include
22 patient-level controls (described in Section 4.1), facility fixed effects, and patient HRR-
by-year fixed effects. Column 1 indicates that receiving care at a PE-owned nursing home
increases the probability of death during the stay and the following 90 days by 1.7 pp, about
10% of the mean. In the context of the health economics literature, this is a very large effect.
This estimate remains stable in magnitude at about 10% of the mean regardless of the time
horizon studied (see Table B.3).
19This follows from Bayes rule and the use of a discrete instrument in this model of the first stage. The
coefficient from a subsample with attribute X is P(M|X)= P(X|M)P(M)/P(X) where M denotes a marginal
PE patient. Dividing by the first stage coefficient for the full sample, P(M), gives us P(X|M)/P(X), the relative
likelihood.
19We calculate the implied cost in statistical value of life-years in Table B.4 Panel A.
We translate the IV coefficients into lives and life-years lost based on the number of index
stays by patients of PE-owned nursing homes during our sample period. Accordingly, we
compute about 20,150 additional deaths due to PE ownership over our twelve-year sample
period. To estimate life-years lost, we rely on observed survival rates for Medicare patients
at all nursing homes. This leads to an estimate of about 160,000 lost life-years.20 Applying
a standard estimate of statistical value of a life-year of $100,000 (Cutler and McClellan,
2001), inflated to 2016 dollars, this implies a mortality cost of $20.7 billion.
The next two columns of Table 4 Panel A consider spending per patient. In our data,
more than 90% of the billed amount is paid by taxpayers through Medicare and patients pay
the balance. The amount billed per nursing home stay increases by 19.5% (column 2; note
it is necessary to exponentiate coefficients larger than .1 when the outcome is logged). As
Table 1 shows, on average PE-owned nursing homes bill $14,800 per stay, while non-PE
nursing homes bill $13,500. This does not seem to reflect additional preventive care that is
compensated for by lower subsequent needs, because the total amount billed for both the
stay and the 90 days following the stay (the episode) increases by about 11%.
The most important robustness test we conduct is a placebo analysis, which probes
whether spurious trends rather than the ownership change might explain the results. We use
Medicare patient-level data from 2002–07, a period with little PE ownership of nursing
homes and little overlap with our main sample. We randomly set the PE dummy to turn on
in 2004 or 2005 for facilities that eventually were acquired by PE firms later. Further, we
discard data for any facility starting with the year it actually got acquired. We recompute
differential distances under these ‘placebo’ assignments and estimate our main IV models.
Table 4 Panel B presents these placebo estimates and reassuringly finds small and
20As life expectancy differs substantially between men and women, we estimate the effect separately by
gender. We calculate the average life expectancy at discharge by gender by observing the actual life span for
each patient in our data. For patients still alive at the end of our sample period, we approximate the year
of death based on patient gender and age using Social Security actuarial tables. We adjust this downward to
account for the fact that decedents tend to be older on average (by about 2 years). We then applied this mean
life expectancy to the number of deaths computed above and obtained the number of life-years lost. This
approach may overstate the true value if the incremental deaths at PE facilities are of older patients. This
approach also understates the true value since we don’t account for the loss in longevity not resulting in death.
20insignificant effects, implying a lack of differential trends prior to acquisition.
Our IV estimates imply that the reduced form effect on mortality and spending should
decline as differential distance grows larger (i.e., relative to the nearest alternative, a PE
facility is farther away). Figure 3 visually confirms this pattern. The figure plots
coefficients from regressing each outcome on indicators for quintile of differential distance,
with the furthest quintile as the reference group using our preferred controls as in the main
specification. By using quantile dummies, this specification is flexible and does not impose
linearity with respect to differential distance. We find the largest effects among patients in
the bottom two quintiles of differential distance, i.e., those located nearest to PE-owned
facilities.
Results from OLS models are presented in Table B.5 and the corresponding event studies
are in Figure B.5. They suggest no pre-trends, consistent with the parallel trends assumption
that underlies our empirical model (i.e., target facilities and control facilities would continue
on parallel trends in the absence of the buyout). We observe a statistically significant, but
much smaller increase in mortality in the OLS model (0.3 pp). This is only one-sixth the
size of the IV estimate, consistent with unobservedly lower risk patients matching with PE-
owned facilities. In a similar vein, we also find small, negative effects on spending (1-2%
decrease) and length of stay (not presented).
5.2 Heterogeneity in the Mortality Effect
This section explores heterogeneity both on observed attributes and on unobserved
resistance to treatment, using a Marginal Treatment Effects (MTE) framework.
5.2.1 Observed attributes
To assess heterogeneity in the IV analysis, we split the sample based on observed
characteristics. We first consider four groups based on patient risk and age. We expect that
higher age is associated with a greater need for attentive but not necessarily high-skill or
complex care, for example helping patients to use the toilet and minimizing infection risk.
21Higher risk – a measure constructed from disease burdens – should be associated with
more need for high-skill, medicalized RN care. Older, high risk patients require the most
intensive and high-skill care. Therefore, we split the sample into four groups around the
median age of 80 and around the high-risk indicator (Charlson score above two). The
results, shown in Table 5 Panel A, document that the effect on mortality is driven by
patients who are low risk, with the most robust result among patients who are low risk but
above-median age. This group accounts for nearly half of the sample. The high risk,
above-median age group also has a large, positive coefficient, but it is noisy. In contrast, the
point estimate for high-risk but below-median age patients is negative and marginally
significant. This suggests that PE-owned nursing homes are able to take better care of more
complex patients, especially when they are on the younger side. But lower risk or older
patients suffer.
We find positive effects among both men and women, but the effect is larger and much
more robust among female patients, who represent 65% of the sample and are on average
older. The effect is also larger among patients from above-median income zip codes.21 It
is also larger among White patients. Finally, the last set of results divide the sample into
three categories corresponding to the patient’s reason for hospitalization prior to the nursing
home stay; we find the largest effect for patients who were hospitalized due to cardiovascular
disease.
There is evidence that for-profit incentives generally and PE ownership specifically are
associated with lower quality of care in more concentrated markets (Gandhi et al., 2020), so
we examine in Panel B whether the effects vary by market competition, using the Herfindahl-
Hirschman Index (HHI) of the hospital referral region (HRR). We find that the coefficient is
larger among nursing homes in below-median HHI areas, but the coefficient is more precise
among nursing homes in above-median HHI areas. As both coefficients are relatively close
to our main estimate, concentration does not appear to be a driving factor.
21We do not observe beneficiary income directly, so we assign individuals to above-median and below-
median income neighborhoods based on their zip code.
225.2.2 MTE Theory and Estimation Approach
The LATE may mask treatment effect heterogeneity across different types of patients. For
example, some patients may benefit from the type of care that is offered by PE-owned
facilities, even though we estimated negative impacts on average for the complier group. It
also ignores the possibility of patient selection on treatment gains. The MTE framework
allows us to examine these dimensions (Heckman and Vytlacil, 2005; Heckman et al.,
2006). It enables us to compute treatment effect parameters of economic interest such as
the Average Treatment Effect (ATE) and Treatment on the Treated (ATT). Unlike the
LATE, these parameters are not specific to the complier group and allow us to make more
general statements regarding the causal effects of PE ownership.
We denote Y0,i and Y1,i as potential outcomes for individual i in the untreated (k= 0) and
treated (k= 1) states, respectively. Treatment in our setting is receiving care at a PE-owned
facility, PEi. We model these potential outcomes Yk,i as a function of observed control
vector Xi and dummies for facility, F j and market-year interactions, Rr,t. Uk,i denotes all
unobserved factors.22
Yk,i = X′
i βk + F j + Rr,t + Uk,i, k= 0,1 (3)
We then propose a latent selection model of how patients choose a PE-owned facility based
on observed and unobserved factors.
PEi = Z′
i δ−Vi,
(4)
PEi = 1 i f PE≥
i 0, PEi = 0 otherwise,
where Z= (X,F,R,D,D2) is a vector including all the controls listed above in Equation (3)
and the differential distance instruments excluded from the outcome equation, Di and D2
i.
We interpret Vi as the unobserved resistance to going to a PE-owned facility. This selection
model imposes monotonicity by using a constant parameter δfor all individuals. Following
the MTE literature, we transform the selection equation into the quantiles of the distribution
of V rather than its absolute values:
22Following Brinch et al. (2017), we assume that the error term Uk,i is normalized to be conditional mean
zero, i.e., E[U|X= x,F= f,R= r]= 0.
23Z′
i δ−Vi ≥0=⇒ Z′
i δ≥Vi =⇒ Φ(Z′
i δ) ≥Φ(Vi), (5)
where Φ is the cumulative distribution function of Vi. We interpret Φ(Z′
i δ) as the propensity
score, the probability that an individual with observed characteristics Zi chooses a PE
nursing home, and denote it as P(Z). Φ(Vi) represents the quantiles of unobserved
resistance to treatment, and is denoted as UD.
Omitting subscripts for simplicity, the MTE is defined as MT E(X= x,UD = u)= E[Y1−
Y0|X= x,UD = u]. The MTE is the treatment gain for an individual with characteristics X=
x, who is in the uth quantile of the resistance distribution. Such individuals are indifferent to
receiving treatment when their propensity score P(Z) equals u.
We make two untestable assumptions to estimate the MTE. The first, as in Section 4.2,
is random assignment of the instrument, conditional on observables. The second
assumption is of functional form. Following the convention in the recent MTE literature
(Brinch et al., 2017; Cornelissen et al., 2018), we assume that the MTE is additively
separable into an observed and unobserved component. This allows the MTE to be
identified over the unconditional support of P(Z) across all values of X rather than the
support of P(Z) conditional on X= x, easing the burden of identifying variation needed
from the data (Carneiro et al., 2011).
MT E(X= x,UD = u)= E[Y1−Y0|X= x,UD = u]
(6)
= x(β1−β0)
observed
+ E[U1−U0|UD = u]
unobserved
Another implication of this assumption is that treatment effect heterogeneity due to X
affects the MTE curve in u only through the intercept. The slope of the MTE curve in u does
not depend on X, facilitating estimation. The potential outcomes model described above
produces the following outcome equation as a function of observables and P(Z) (Carneiro
et al., 2011).
E[Y|X,F,R,P(Z)= p]= X′β0 + F + R + X′(β1−β0)p + K(p), (7)
where K(p) is a nonlinear function of the propensity score. The derivative of this outcome
equation with respect to p estimates the marginal treatment effect at X= x and UD = p
24(Heckman et al., 2006).
We first estimate the selection model in Equation (4) using a linear probability model and
ˆ
obtain ˆ p = Z′
δ. Figure 4 Panel A presents the variation in the estimated propensity score.
We collapse the data to percentiles of differential distance, D and plot a non-parametric
fit of P(Z) values against the corresponding percentile means of D. This shows a similar
pattern first observed in Figure 2—the probability of going to a PE-owned facility declines
nearly monotonically as differential distance increases. However, this figure masks the full
support of the distribution of P(Z), which extends over the entire unit interval. Figure 4 Panel
B highlights the overlap in distribution of the propensity scores for treated and untreated
patients by plotting histograms for the two groups against P(Z) on the X-axis. We use
log scales on the Y-axes since there are large numbers of observations at the two extremes
of propensity score. The figure confirms that the treated and untreated groups overlap in
distributions over nearly the entire unit interval, enabling the estimation of the unconditional
ATE without the need for extrapolation (Basu et al., 2007). We then estimate the outcome
Equation (8) below, assuming K(p) is a polynomial in p of degree S.
Y= X′β0 + F + R + X′(β1−β0) ˆ p +
S
ρsK( ˆ p) + ϵ. s=2
(8)
The MTE curve is the derivative of Equation (8) with respect to ˆ p. In our baseline model
we set S= 2, but test robustness to using higher order polynomials. Standard errors are
obtained by block bootstrap, clustering by facility.
5.2.3 MTE Results
We estimate Equation (8) and confirm the presence of selection on unobserved resistance by
testing the joint significance of the coefficients ρs on the higher order terms of the polynomial
in p (Heckman et al., 2006). The coefficient on p2 is highly statistically significant (p value
<0.01), confirming patient selection into PE facilities on unobserved resistance.
Figure 4 Panel C presents the MTE curve along with 90% confidence intervals. Our
primary approach uses a second degree polynomial, so the MTE curve is linear in
unobserved resistance (u). Since it is downward sloping, there is reverse selection on
25treatment gains; that is, individuals with the least resistance to going to a PE facility
experience the worst mortality effects of nearly 4 pp. In contrast, individuals with the
highest resistance experience marginally negative (i.e., beneficial) effects. The MTE values
are not statistically significant for individuals with above median resistance to treatment.
The figure also plots the ATE, which is 1.3 pp (s.e. 1.4 pp). To test sensitivity to the
linearity assumption, we also estimate the MTE curve with 3rd, 4th, and 5th degree
polynomials. Figure B.6 Panel B shows that the curve remains downward sloping
regardless of the polynomial.
We aggregate the marginal treatment effects using the appropriate weights to obtain
various treatment effect parameters such as the unconditional ATE and ATT (Cornelissen et
al., 2016). Given the downward sloping nature of the MTE curve, we expect the average
effect on the treated to be higher than that for the untreated. Figure 4 Panel D presents the
weights to apply to the MTE values to compute the ATT and ATUT. Accordingly, we
estimate an ATT of 3.1 pp (s.e. 0.9 pp) and an ATUT of 1.0 pp (0.9 pp). Only the ATT is
statistically significant among the three treatment effect parameters.
There are two key takeaways from this analysis. First, the ATE implies that a randomly
chosen Medicare patient from our sample would experience an increase of 1.3 pp in the
probability of short-term mortality if she chose a PE-owned nursing home. While about a
third lower than the LATE estimate, it nevertheless implies a large number of deaths in a
counterfactual where all Medicare short-stay patients receive care at a PE-owned facility.
Second, the MTE curve implies reverse selection on gains and that some patients – those
with greater resistance to treatment – experience improvements in mortality if they choose
a PE-owned facility, though the negative MTE values are not statistically significant. This
pattern is consistent with the heterogeneity in treatment effects on observed attributes. For
example, we find a large and statistically significant increase in mortality for individuals
residing in zip codes with greater than median income (see Table 5 row 3). Individuals in
richer neighborhoods are also about 20% more likely to choose PE-owned facilities – their
mean propensity score is 12 pp versus 10 pp for patients from neighborhoods with income
below the median. In contrast, we find a smaller and statistically insignificant effect for
26individuals in lower income neighborhoods.
5.3 Patient Well-Being and Mechanism Tests
If the effect on short-term mortality is related to lower patient welfare, we expect to see
consistent evidence using other wellbeing measures. Therefore, we also use the IV model
to assess effects on the four clinical measures of wellbeing that CMS uses as outcomes for
short-stays when computing Five Star ratings (surprisingly, mortality is not one of them).
The first is whether a patient starts taking antipsychotic drugs. As discussed in Section
3, antipsychotics are discouraged in the elderly due to their association with mortality and
the greater efficacy of behavioral interventions. We find that going to a PE-owned nursing
home increases the chances of starting antipsychotics by 3 pp, or 50% of the mean (Table
6 column 1). Using an estimate from the literature on how antipsychotic medications affect
mortality, this coefficient implies that about 15% of the total effect on mortality is potentially
attributable to starting antipsychotics.23
We also find a positive effect on experiencing worsening mobility, which increases by
4.3 pp, or about 8% of the mean (Table 6 column 2). We do not find a significant effect
on the third measure – developing ulcers – though the coefficient is positive (column 3).
Fourth, there is a positive effect on increasing pain intensity of 2.7 pp, which is 10% of the
mean. Figure B.5 presents the corresponding event studies and indicate no differential pre-
trends.24 Overall, the evidence of harmful effects on other measures of patient wellbeing are
comfortingly consistent with the estimated effects on mortality.
Thus far we have assumed that ownership type explains any effects of PE buyouts.
Alternatively, PE ownership could bring economies of scale or corporatization, which are
23Several clinical studies have examined the harmful effects of antipsychotic prescribing for the elderly.
The most relevant study for our purposes is by Schneider et al. (2005), who perform a meta-analysis of fifteen
randomized controlled trials (11 from nursing homes) that studied the effects of antipsychotics on mortality for
elderly patients. They report a 50% increase in mortality. The trials evaluated mortality at durations averaging
about 3 months, coincidentally matching our mortality measure. Applying a 50% increase in mortality to our
setting implies an 8 pp increase in 90-day mortality on a mean of 17 pp. We apply this elevated mortality
effect to the 3 percent additional patients at PE facilities who receive antipsychotics. This implies an increase
in mortality of 8 x 0.03= 0.24 pp for PE patients on average.
24Results using OLS models are in Table B.5B. They are typically smaller in magnitude (except ulcers),
consistent with selection leading to downward bias in OLS.
27the explanation that Eliason et al. (2020) propose for negative effects of dialysis center
mergers. To test this hypothesis, we conduct three tests in Table 7. The first adds to our
main model a control for being a chain versus an independent facility. If our effects are
explained by the “rolling-up" of independent facilities into more efficient chains, the
estimates should attenuate. Instead, they are essentially unchanged. The second test
excludes the top two deals—the buyouts of the very large Genesis Healthcare and Golden
Living chains (both have more than 300+ facilities). The coefficient is larger, implying that
our result is not driven by the very largest chains. The most important test is in row 4,
where we use only the top five deals to define PE ownership. In these deals, the target
chains already owned more than 100 facilities and stayed nearly the same size over the
sample period. Therefore, in this model chain size is held constant and we evaluate the
effect of a change in ownership. Again, the effect is larger than in the full sample. In sum, it
does not seem that chain corporate structures or synergies in large firms explain our results.
Another concern is whether the results are spuriously capturing the quality difference
between for-profit and nonprofit nursing facilities. About 20% of the patients receive
treatment at a non-profit facility. By definition these facilities are part of the control group.
We test the sensitivity of our main estimate to excluding these facilities from the sample
altogether. Row 5 presents the corresponding results and shows that the estimate reduces
about 20% in magnitude but remains statistically significant.
The remaining rows of Table 7 report robustness tests that vary the controls and market
definitions. If the instrument does not randomly assign patient risk, we expect patient
controls to substantially affect the results. Instead, the results are robust to alternative
controls, consistent with random assignment. The first test in this group (row 6) includes
zip-year socioeconomic controls. The coefficients decline only slightly. The next two rows
use the more granular HSAs and counties, respectively, to define patient markets instead of
HRRs. The final row omits all patient controls, estimating larger effects, but well within
two standard errors of the main estimate. Overall, the results are quite stable.
286 Operational Changes
This section uses facility-level data to explore operational changes that could help explain
the adverse patient welfare effects described in the previous section.
6.1 Empirical Strategy
For outcomes available only at the nursing home level, we cannot instrument for patient
selection and the best possible research design therefore is differences-in-differences. We
use variants of the following specification:
Yj,t = αj + αt + βPE j,t + P′
j,t γ1 + M′
j,t γ2 + εj,t (9)
PE j,t takes a value of one if facility j is PE-owned in year t. The coefficient of interest is
β, which captures the relationship between PE ownership and the outcome Yj,t. We include
facility (αj) and year fixed effects (αt). We retain all facilities in our preferred specification,
but the results are robust to limiting the sample to for-profit facilities. The vector Pj,t includes
three controls for facility-level patient mix and Mj,t includes five county-level controls for
time-varying market attributes.25 As there may be concern that control variables could be
affected by PE ownership, we also present results without any controls.
The identifying assumption is that PE targets and control facilities would continue on
parallel trends in the absence of the acquisition. We assess whether there are differential
pre-trends using event study figures, which plot the coefficients βs from estimating Equation
(10) below.
Yj,t = αj + αt +
βsDeal Yearj,s + P′
j,t γ1 + M′
j,t γ2 + εj,t (10)
s 0
25Patient mix controls: Case Mix Index (CMI) is a composite measure of patient risk based on medical
history of diagnosis or treatment for a large number of conditions. Second, Acuity index is a measure of
patient risk computed using the patient’s assessed Activities of Daily Living (ADL) scores. In both cases, a
greater value indicates a riskier patient cohort for the nursing home. We winsorize both the CMI and Acuity
Index at the 1% and 99% level in each year. The third control is the share of the facility’s patients who
are Black. County-level controls: Herfindahl Hirschman Index (HHI) based on shares of beds, number of
for-profits, number of chain-owned, number of hospital-based, and number of overall facilities. These are
calculated using a leave-one-out procedure from the facility-level data.
29Deal Yearj,s is an indicator that is one in year s relative to the buyout year for facility j, and
zero otherwise. The remaining terms are as defined above for Equation (9).
6.2 Results
We consider three types of operational channels. The first two explicitly concern facility
quality, while the last pertains to financial strategies particular to the PE industry. All the
results are presented in Table 8. For each outcome, the top row of coefficients are from
specifications with only facility and year fixed effects, while the bottom row adds the full set
of patient and market controls. Event studies are in Figures 5 and 6.
6.2.1 Compliance With Standards and Staff Availability
First, we consider compliance with care protocols in Panel A of Table 8. Our outcome of
interest is the facility-level Five Star rating, which varies from one (worst) to five (best).
After PE buyouts, the Deficiency rating declines by 0.08 points (column 1), which is about
3% of the mean and 7% of the standard deviation (the most relevant measure given how this
variable is constructed). This rating reflects whether the facility is satisfying care protocols
such as storing and labeling drugs properly, disinfecting surfaces, as well as other aspects
of care such as ensuring resident rights and avoiding patient abuse. The Overall rating
similarly declines (column 2). Figure 5 presents event studies for each outcome. There are
no pre-trends, consistent with the identifying assumption, and the negative effects appear
immediately after the change in ownership and persist for at least five years.26
In Panel B, we assess effects on nursing staff hours per patient-day, a well-established
measure of nursing home quality that accounts for changes in patient volume. Column 1
shows a modest decline of 0.05 hours in aggregate staff hours (1.4% of the mean). This
aggregate effect masks larger changes for different types of nurses that offset each other.
There is a decrease in ‘front line’ caregivers (CNAs and LPNs), shown in columns 2 and
26The Overall rating has three components: the Deficiency rating, a Quality rating based on metrics
computed using claims data and clinical assessments, and a Staffing rating, which is based on staffing measures
evaluated in Panel B. Since we assess quality and staffing changes more granularly, we do not present the effects
on these components, but we find negative, significant effects of equal or larger magnitudes there as well.
303, respectively. Together there is a decline of around 0.09 hours for these two groups (3%
of the mean). In contrast, there is an increase in use of Registered Nurses (RNs) by about
0.04 hours (8%). The event studies in Figure 5 again reveal no pre-trends and indicate more
immediate declines after the deal in front-line staffing, while the increase in RN staffing
appears starting in the third year after the buyout.27 The increase in RN staff hours does not
compensate for the decline in lower skilled nurse hours because RNs account for a small
fraction of all staff hours. Medicare cost reports indicate that CNAs and LPNs receive an
hourly wage that is about 40% and 70% respectively of the wage paid to RNs, which is
around $35 per hour. Unfortunately, we cannot observe whether facilities are taking cost
reduction steps such as using more part-time labor and reducing individual shifts.
The existing literature helps to connect the effects on nurse availability with the
estimated effect on mortality. Tong (2011) exploits an increase in minimum nurse staffing
regulation in California and finds a decline in on-site patient mortality due to greater
availability of frontline nurses. Applying her estimates in our setting, the estimated decline
in frontline nurse staffing predicts an increase in mortality of 0.25 pp.28 The findings on
increased use of antipsychotics and lower nurse availability may be related. Grabowski et
al. (2011) note that antipsychotics are believed to substitute for nurse care and show that
when nursing homes increase wages, inappropriate use of antipsychotics decreases.
Therefore, it is intuitive that lower staffing – in particular low-skill staffing – would be
associated with increases in adverse conditions related to lack of attention, such as more
use of antipsychotics and lower mobility. The two channels additively predict an increase
in mortality of 0.5 pp in our setting (about 30% of our mortality effect). However, this may
be an underestimate if they produce larger effects when they interact.
The increase in RN availability is consistent with the negative effects on mortality being
driven by older rather than more complex patients. RN staff are most relevant for the more
27We report the results of robustness tests in Table B.6, which include controls for chains, excluding the top
two deals, and including only for-profit nursing homes.
28Tong (2011) reports a 15% decline in mortality due to an increase in nurse availability of one hour per
resident-day. Since we estimate a decline of 0.09 hours, this predicts an increase of 0.09 x 15= 1.4% of the
mean, or 0.24 pp. More recently, Ruffini (2020) exploits variation in minimum wage requirements to isolate
the effects of nurse staffing changes on quality and also finds mortality effects.
31medicalized aspects of care, while front line nurses support daily living activities such as
preventing infections and turning patients in bed. One possibility is that managers may
have looked for ways to cut overall labor costs while changing the mix of nursing staff
capability to maintain quality and patient experience, as RNs are crucial to nursing home
quality (Zhang and Grabowski, 2004; Lin, 2014). An alternative explanation is the
regulatory focus on RNs. For example, CMS uses the availability of RNs to determine
eligibility for Medicare reimbursement.29 Given the tight regulatory scrutiny of RN
availability, it is difficult to reduce staffing levels in this category.
To explore whether the declines in staff availability and quality are related, we compare
changes in staff availability and Five Star ratings within target facilities around the PE buyout
event. This analysis recovers correlations and does not imply causality, so we present the
raw data in bin-scatter plots. Figure B.7 shows the change in Five Star rating over the
three years around PE acquisition on the Y-axis against the change in aggregate staff hours
per patient day during the same period on the X-axis. The plots show that facilities which
experienced larger declines in staff availability also experienced greater declines in ratings.
The patterns are consistent across rating types and suggest that cuts to nursing staff may be
an important channel to explain the quality declines.
6.2.2 Finances and Operations
Our final analysis uses CMS cost reports to analyze key sources of expenditure related to
the PE business model. We begin by noting that nursing homes are widely known to have
relatively low and regulated profit margins, often cited at just 1-2%.30 Our data on nursing
home cost reports submitted to CMS indicate that nursing homes report negative operating
margins on average, and PE-owned nursing homes are not on average more profitable. In
unreported analysis, we see no effect of buyouts on net income or overall revenue or costs.
29Specifically, such facilities are defined by having “an RN for 8 consecutive hours a day, 7 days
a week (more than 40 hours a week), and that there be an RN designated as Director of Nursing
on a full time basis.” See https://www.cms.gov/Regulations-and-Guidance/Guidance/Manuals/
Downloads/som107c07pdf.pdf.
30http://www.medpac.gov/docs/default-source/data-book/jun17_databookentirereport_
sec.pdf
32This raises the question of how PE firms create value from nursing home investments.
There are three types of firm expenditures that the academic literature and popular press
particularly associates with profits for PE owners. The first is what are often termed
“monitoring fees" charged to portfolio companies. In the CMS cost reports, these are listed
as “management fees”—charges to the nursing home for being owned and managed by a
PE firm.31 Metrick and Yasuda (2010) note that these are thought to be between 1-5% of
EBITDA. Our data suggest that they increase over time after buyouts, as shown in Figure 6
Panel A, where the fees are flat before the buyout, and then rise dramatically afterwards.
Table 8 Panel C column 1 indicates that on average, management fees increase by 7.7%
after acquisition (we exponentiate coefficients in this panel as the outcomes are in logs).
The second type of expenditure is lease payments. The value of underlying real estate
is frequently cited as a reason that nursing homes and other typically low-margin assets can
be profitable investments, because the investor can sell the real estate to a related company
or to a third party (Dixon, 2007; Keating and Whoriskey, 2018; Brown, 2019). Cash from
the real estate sale can be disbursed as profits to the PE fund. A cash inflow early in the
life of the investment is particularly beneficial to the fund’s Internal Rate of Return, a key
performance metric. The nursing home assumes the obligation of future rent payments. As
an example, a New York Times report on the nursing home industry notes that:
“[PE] investors created new companies to hold the real estate assets because the
buildings were more valuable than the businesses themselves, especially with
fewer nursing homes being built. Sometimes, investors would buy a nursing
home from an operator only to lease back the building and charge the operator
hefty management and consulting fees” (Goldstein et al., 2020).32
31 In their summary of buyout fund economics, Metrick and Yasuda (2010) write that “we think of
monitoring fees as just another way for BO funds to earn a revenue stream.” These fees should not be confused
with the usual 2% of fund value that General Partners earn each year for managing Limited Partners’ capital,
before profits from investments.
32Two examples further illuminate these types of transaction. First, the HCR Manorcare deal discussed in
Section 2.2, where the chain’s real estate assets were spun off and sold shortly after the acquisition by the
Carlyle Group. Second, at a Congressional hearing the executive director of the Long-Term Care Community
Coalition said “more and more with entities buying up nursing homes, they have no experience in the business,
they sell out the underlying property” (Brown, 2019).
33Consistent with this strategy, column 2 shows that facility building lease payments increase
dramatically by about 75% after PE acquisitions. Figure 6 Panel B confirms the lack of
pre-trends and the increase post-buyout.
The third type of expenditure is interest on debt. While not a direct source of PE profits,
debt is tightly related to the overall PE model for creating value. Metrick and Yasuda
(2010) note that the ratio of debt to equity in a buyout deal is typically around 5:1. The
interest payments become a cost to the portfolio company. In Figure 6 Panel C, we see that
like the previous two outcomes, interest payments are flat before the buyout and then rise
dramatically afterwards. Column 3 indicates that the increase is about 325%.
Finally, we find that cash on hand declines after the buyout by 38%. Unlike the other
outcomes, the event study in Figure 6 Panel D indicates that cash on hand initially
increases after the buyout as profits increase and cash is injected, perhaps to invest in
efficiency improvements. However, as the strategies for returning profit to the investors are
implemented, such as selling the real estate and thus requiring the operator to take on lease
payments, the cash on hand turns negative. This could make the nursing home less
well-equipped to manage sudden shocks such as, for example, needing to buy personal
protective equipment following an infectious disease breakout.
Taking the results on nurse availability together with the estimated effects on interest,
lease, and management fees payments, we infer that PE ownership shifts operating costs
away from staffing towards costs that are profit drivers for the PE fund. To our knowledge,
this paper offers the first instance in the literature on PE in which these three profit drivers
have been documented systematically.
The final outcome we explore is patient capacity and volume. Table B.7 column 1 finds
no measurable change in the number of beds, which may partly reflect state regulations
restricting expansions. Admissions increase by 3.5%, or 6.5 patients per year for the average
facility (column 2). However, we interpret this effect with caution since the corresponding
event study suggests a pre-trend (Figure B.8B). The apparent disconnect between demand
and quality of care may reflect information frictions in observing nursing home quality, as
discussed earlier (Arrow, 1963; Grabowski and Town, 2011; Werner et al., 2012).
34Higher admissions raise the question of whether PE ownership increases overall access
to nursing home care, providing care for individuals who would not otherwise have gone
to a nursing home. To test whether this is the case, we assess the effects of PE entry into
a nursing home market, using the HRR definition. Table B.7 column 3 shows that there is
no effect of initial PE entry on admissions at the market level, corroborated by flat patterns
in the event study (Figure B.8C). Hence, the data are more consistent with the facility-level
admissions increase reflecting business stealing.
7 Conclusion
This paper studies PE buyouts in healthcare, an important sector where PE activity has
increased dramatically, generating policy debate. Nursing homes are a useful setting
because they have particularly high levels of for-profit ownership and subsidy and have
experienced extensive PE investments. In an instrumental variables design incorporating
facility fixed effects, we address both targeting and patient selection challenges to
identification. We find that going to a PE-owned facility increases 90-day mortality by
about 10% for short-stay Medicare patients, while taxpayer spending over the 90 days
increases by 11%. Furthermore, we document declines in nurse availability per patient and
in measures of compliance with Medicare’s standards of care. We also find a corresponding
increase in operating costs that tend to drive profits for PE funds.
There are many channels for future work. Although our results imply PE ownership
reduces productivity of nursing homes, it may have more positive effects in other sectors
of healthcare with better functioning markets. Beyond healthcare, there has been significant
PE investment in sectors such as education, defense and infrastructure, which like healthcare
rely on high levels of government subsidy but are characterized by opaque product quality.
Further work is needed to determine how government programs can be redesigned to align
the interests of PE-owned firms with those of taxpayers and consumers.
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42Figures and Tables
Figure 1: Private Equity Ownership in Healthcare
A: PE Deals in Healthcare B: PE Deals in Eldercare
C: Number of Facilities and Patients Acquired D: Percentage of Facilities and Patients Acquired
Note: This figure shows PE deals in health care over time. Panels A and B present the total capital invested
(left axis) and number of transactions (right axis) by PE firms in healthcare and eldercare, by year. Panels C
and D focus on the number of active nursing homes owned by PE firms in each year. Panel B presents the
number of PE-owned facilities (left axis) and patients admitted at these facilities (right axis). Note that the total
number of facilities ever bought by PE firms is larger (1,674) than what is plotted here since some of these
facilities closed or went back to non PE ownership over time. Panel D presents these trends as a percentage of
total number of facilities and patients admitted, respectively.
43Figure 2: Patient Characteristics with Differential Distance
A: High Risk Patients
B: Stay at PE Nursing Home
Note: This figure presents scatter plots of patient characteristics against differential distance to the nearest PE
facility. The independent variable is the difference in distance (in miles) of the nearest PE nursing home to the
nearest non-PE nursing home for the patient. The dependent variable in Panel A is an indicator for the patient to
have a Charlson Co-morbidity Index (based on diagnoses recorded in hospital inpatient and outpatient claims
over the 3 months before admission to nursing home) greater than 2, and in Panel B is an indicator for the
nursing home being PE-owned. The data was collapsed into 20 equal sized bins and we plot the means of
residuals in each bin that were obtained from models including facility and patient HRR x Year fixed effects,
and patient demographics: age, race, gender, maritial status, and an indicator if patient is dual eligible. The
figures also present quadratic fitted lines for these plots. Each plot also presents the slope coefficient (per 10
miles of differential distance) with the corresponding standard error. Standard errors are clustered by facility.
44Figure 3: Patient Outcomes and Differential Distance
A: Mortality (Stay + 90 Days) B: Log Amount Billed per Patient Stay
C: Log Amount Billed per Patient Stay + 90 Days
Note: This figure presents results from reduced form regressions for patient-level outcomes on the instrument,
differential distance. Each blue point in the figure represents a coefficient βs, obtained by estimating the
equation Yi = αm,t + αj + 5
s=2 βs 1(QDD = s)i + γ1 Xi + +ϵi, where 1(QDD = s)i is an indicator for the qth
quintile of differential distance. The highest quintile group, i.e., individuals relatively furthest away from a PE
facility, is the reference group. Log total payment in Panel B refers to the total payment for the index nursing
home stay. Standard errors are clustered by facility.
45Figure 4: Marginal Treatment Effects
P(z)
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-20 -10 0 10 20 30 40 50 60 70
Differential distance (miles)
A: First stage B: Common Support
0.050
MTE
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
0.050
0.040
0.040
Weights
0.030
0.020
0.010
0.000
0.030
0.020
Treatment effect
0.010
0.000
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Unobserved resistance to treatment
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Unobserved resistance to treatment
MTE 90% CI ATE (.013)
TT weights TUT weights
ATT (.031) ATUT (.01)
C: MTE curve
D: ATT and ATUT
Note: This figure presents results pertaining to Marginal Treatment Effects (MTE) analysis using the Medicare
patient-level data. Panel A presents the ‘first stage’ fit of predicted probability of treatment or propensity score,
w.r.t the instrument. Panel B presents the overlap in distributions of PE and non-PE groups by propensity
score. This plot uses a log scale due to the large number of non-PE patients with low propensity. Appendix
figure B.6A presents the corresponding plot using a linear scale. Panel C presents the MTE curve with 90%
confidence intervals obtained using block bootstrap and the Average Treatment Effect (ATE) estimate. Panel D
presents the weights for the Average Treatment on the Treated (ATT) and Average Treatment on the Untreated
(ATUT) and the corresponding estimates. Section 5.2.2 presents details of the MTE estimation.
46Figure 5: Aggregate Quality and Staffing Outcomes
A: Deficiency Survey Rating B: Overall Rating
C: Staff Hour per Patient Day D: Nurse Asst. per Patient Day
E: Lic. Nurse per Patient Day F: Registered Nurse per Patient Day
Note: This figure presents event studies on quality of care measures (Five Star ratings) and Staffing around the
time a nursing home experiences a PE buyout. Each point in the figures represents the coefficient βs obtained
by estimating Equation (10) as discussed in Section 6. Year= -2 is the omitted point. In Panels A and B, we
present effects on the Five-star ratings awarded by CMS - deficiencies identified by independent contractors in
audits and overall rating, respectively. A negative effect on ratings implies a decline in quality. Panels C to F
present results on nurse staffing per-patient for all staff, nurse assistants, licensed nurses, and registered nurses
respectively. All models include facility and year fixed effects, patient mix and market controls, as described
in Section 6.1. All dependent variables are winsorized at 1 and 99% level. Standard errors are clustered by
facility.
47Figure 6: Facility Finances
A: Log Management Fee Cost B: Log Building Lease Cost
C: Log Interest Cost D: Log Cash on Hand
Note: This figure presents event studies on facility finances around the time a nursing home experiences a
PE buyout. Each point in the figures represents the coefficient βs obtained by estimating Equation (10) as
discussed in Section 6. Year= -2 is the omitted point. Panels A to D present results on the log of management
fee cost, building lease cost, interest cost, and cash on hand, respectively. All models include facility and
year fixed effects, patient mix and market controls, as described in Section 6.1. All dependent variables are
winsorized at 1% and 99% levels. Standard errors are clustered by facility.
48Table 1: Descriptive Statistics
All Not PE-owned PE-owned
Mean SD Count Mean Count Mean Count
A. Facility Level Attributes
Overall Five-Star Rating 3.17 1.30 138,204 3.20 127,441 2.83 10,763
Deficiency Five-Star Rating 2.84 1.25 138,204 2.86 127,441 2.62 10,763
Staff Hours per Pat. Day 3.59 1.49 284,108 3.60 271,118 3.38 12,990
Nurse Assistant Hours per Pat. Day 2.28 0.79 284,108 2.29 271,118 2.06 12,990
Licensed Nurse Hours per Pat. Day 0.82 0.46 284,108 0.82 271,118 0.82 12,990
Registered Nurse Hours per Pat. Day 0.46 0.57 284,108 0.46 271,118 0.49 12,990
Number of Beds 104.48 56.60 284,108 104.11 271,118 112.34 12,990
Admissions 184.16 166.97 284,108 180.40 271,118 262.47 12,990
Ratio Black 0.10 0.17 284,108 0.10 271,118 0.12 12,990
Ratio Medicaid 0.60 0.24 284,104 0.60 271,114 0.60 12,990
Ratio Medicare 0.15 0.17 284,104 0.15 271,114 0.18 12,990
Ratio Private 0.25 0.19 284,104 0.25 271,114 0.22 12,990
Management Fees (2016$) 7,076 120,673 231,795 6,001 219,231 25,833 12,564
Building Lease (2016$) 5,860 80,223 231,826 4,825 219,262 23,919 12,564
Interest Expense (2016$) 12,911 163,562 231,855 5,588 219,291 140,733 12,564
Cash on Hand (2016$) 1,110,000 10,600,000 231,811 1,150,000 219,257 516,772 12,554
B. Medicare Patient Attributes
Age 81.41 8.10 7,365,953 81.46 6,668,539 80.92 697,414
Female 0.64 0.48 7,365,953 0.64 6,668,539 0.62 697,414
Black 0.08 0.27 7,365,953 0.08 6,668,539 0.09 697,414
White 0.88 0.32 7,365,953 0.88 6,668,539 0.88 697,414
Married 0.34 0.47 7,365,953 0.34 6,668,539 0.35 697,414
Charlson Score (Previous) > 2 0.27 0.44 7,365,953 0.27 6,668,539 0.29 697,414
Cardio-Vascular Disease 0.18 0.39 7,365,953 0.18 6,668,539 0.18 697,414
Injury 0.19 0.39 7,365,953 0.19 6,668,539 0.19 697,414
Other 0.63 0.48 7,365,953 0.63 6,668,539 0.63 697,414
Dual Eligible 0.18 0.38 7,365,953 0.18 6,668,539 0.17 697,414
Differential Distance (Miles) 14.87 16.70 7,365,953 16.21 6,668,539 2.11 697,414
Mortality (Stay + 90 Days) 0.17 0.38 7,365,953 0.17 6,668,539 0.18 697,414
Starts Anti-Pyschotics 0.06 0.23 7,365,953 0.06 6,668,539 0.06 697,414
Mobility Reduces 0.54 0.50 7,365,953 0.53 6,668,539 0.62 697,414
Develops Ulcers 0.09 0.28 7,365,953 0.09 6,668,539 0.09 697,414
Pain Intensity Increases 0.27 0.45 7,365,953 0.27 6,668,539 0.30 697,414
Amount Billed per Patient Stay (2016$) 13,600 12,200 7,365,953 13,500 6,668,539 14,800 697,414
Amount Billed per Patient Stay + 90 Days (2016$) 21,100 20,100 7,365,953 20,900 6,668,539 22,600 697,414
Note: This table presents descriptive statistics for key variables used in the analysis. Panel A presents
descriptives on facility-level data for all nursing homes over the years 2000–17 while Panel B presents patient-
level data for Medicare patients with index stays over the years 2005–16. A unit of observation is a facility-year
in Panel A and a unique patient in Panel B (since we retain only the first stay per patient). Columns 1, 2 and 3
present means, standard deviations and number of observations for the full sample. We categorize facilities into
two groups. Columns 4 and 5 present means and number of observations at facilities that never experienced
a PE acquisition or before PE acquisition during our sample period. Columns 6 and 7 present corresponding
values for facilities in the post-buyout period. For most variables, about 10% of the observations pertain to
facilities that experienced a PE acquisition. Sample sizes differ across variables in Panel A since they were
sourced from multiple sources or in some cases were reported only for more recent years. In Panel A, all
continuously varying variables were winsorized at the 1% and 99% levels. We compute the Charlson Co-
morbidity Index using co-morbidities diagnosed in hospital inpatient and outpatient claims (first 10 dx codes)
over the 3 months prior to, but not including, the index stay. Spending values in Panel B are winsorized at the
99% level and deflated to be in 2016 dollars. ‘Total’ billing includes hospital inpatient, outpatient including
emergency department, and nursing home stay spending over the 90 days following discharge from the index
stay and includes the index stay. The following patient-level variables were sourced from the Minimum Data
Set (MDS): marriage, antipsychotics, mobility, and pressure ulcers. Medicare patients that could not be merged
into the MDS (94% match rate) were dropped from the sample. Facilities with less than 100 Medicare patients
over the entire period were omitted from the patient-level sample. If any of the MDS variables was missing,
then we set the respective indicator to zero. We exclude patients facing a differential distance of greater than
70 miles, approximately the 95th percentile value, or below -70 miles.
49Table 2: Patient-Level Analysis: First Stage
(1) (2) (3) (4) (5)
1(PE) 1(PE) 1(PE) 1(PE) 1(PE)
Differential Distance -0.0480*** -0.0480*** -0.0479*** -0.0454*** -0.0419***
(In 10 Miles) (0.002) (0.002) (0.002) (0.002) (0.002)
(Differential Distance)2 0.0062*** 0.0063*** 0.0062*** 0.0059*** 0.0055***
(In 10 Miles) (0.000) (0.000) (0.000) (0.000) (0.000)
Market Controls Y
Patient Controls Y Y Y Y
Facility FEs Y Y Y Y Y
Patient FEs Level HRR x Year HRR x Year HRR x Year HSA x Year County x Year
Observations 7,365,934 7,365,934 7,358,129 7,365,752 7,365,246
Y-Mean 0.09 0.09 0.09 0.09 0.09
F-Stat 224 224 222 220 203
Note: This table presents estimates of the relationship between PE ownership of the nursing home and the
patient’s differential distance. Each cell presents the coefficient β obtained by estimating Equation (1). The
independent variable is the difference in distance (both linear and quadratic, in 10 miles) to the nearest PE
nursing home and the nearest non-PE nursing home for the patient. This is calculated based on distances
between the respective zip code centroids. The outcome variable is an indicator for whether the nursing home
serving the patient is PE-owned (=1 if PE-owned, 0 otherwise). Column 1 controls for facility and patient
market (Hospital Referral Region) x Year fixed effects. Column 2 (our preferred specification) adds controls
for patient risk controls (indicators for 17 pre-existing conditions used to define the Charlson Co-morbidity
Index inferred from claims over the three months prior to admission, and sex, age, race, marital status, and
an indicator if patients are dual eligible). Column 3 adds controls for patient zip-year characteristics: median
household income, the shares of the population that are white, that are renters rather than home-owners, that
are below the Federal poverty line, and that are enrolled in the medicare advantage program. Column 4 uses
the same controls as in col. 2 but defines patient market using a narrower market definition: Health Service
Area (HSA) instead of HRR. Column 5 uses the same controls as in col. 2 but defines patient market using a
narrower market definition: County instead of HRR. Standard errors are clustered by facility.
50Table 3: Balance of Patient Characteristics
(1) (2)
Patient Attribute DD < Median DD > Median
Differential Distance 2.70 27.04
PE-owned Nursing Home 0.17 0.02
Age 81.40 81.42
Female 0.64 0.64
Black 0.09 0.07
Married 0.35 0.34
Dual Eligible 0.16 0.19
AMI 0.08 0.08
Congestive Heart Failure 0.22 0.24
PVD 0.05 0.05
CEVD 0.13 0.14
Dementia 0.04 0.05
COPD 0.21 0.23
Rheumatoid Arthritis 0.03 0.03
Peptic Ulcer 0.02 0.02
Mild Liver Disease 0.01 0.01
Diabetes 0.21 0.22
Diabetes + Complication 0.04 0.04
Paraplegia 0.03 0.03
Renal Disease 0.14 0.13
Cancer 0.09 0.08
Severe Liver Disease 0.01 0.01
Metastatic Cancer 0.04 0.04
AIDS 0.00 0.00
Number Of Patients 3,683,135 3,682,818
Note: This table presents the balance in patient attributes with respect to the
instrument: differential distance. We divide patients into two groups based
on whether their differential distance is below or above the median value
(8.9 miles). Recall that differential distance (DD) is the difference between
distance to the nearest PE nursing home and the nearest non-PE nursing
home for the patient. Column 1 presents the means of patient characteristics
for patients with DD below the median value, while Column 2 presents
the means for patients with DD greater than the median. Characteristics
include four demographics and 17 pre-existing co-morbidity indicators used
to compute the Charlson Co-morbidity Index. Paraplegia includes both partial
and complete paralysis. We generated indicators for the 17 disease groups
using the ‘charlson’ command in Stata, available at http://fmwww.bc.
edu/RePEc/bocode/c/charlson.html. We considered diagnosis codes
on hospital inpatient and outpatient claims over the 3 months prior to, but not
including, the index nursing home stay.
51Table 4: Patient-Level Analysis: IV Results
A: Main Results
(1) (2) (3)
Mortality Log Amount Billed Log Amount Billed
(Stay + 90 Days) Per Patient Stay Per Patient Stay + 90 Days
1(PE) 0.0168** 0.1777*** 0.1054***
(0.007) (0.028) (0.024)
Observations 7,365,934 7,365,934 7,365,934
Y-Mean 0.17 9.07 9.57
F-Stat 224 224 224
B: Placebo Analysis
(1) (2) (3)
Mortality Log Amount Billed Log Amount Billed
(Stay + 90 Days) Per Patient Stay Per Patient Stay + 90 Days
1(PE) 0.006 -0.015 -0.016
(0.004) (0.018) (0.016)
Observations 7,159,535 7,159,535 7,159,535
Y-Mean 0.18 9.01 9.51
F-Stat 441 441 441
Note: This table presents estimates of the relationship between PE ownership and
patient health and spending. In Panel A, each cell presents the coefficient β obtained
by estimating Equation (2) by 2SLS. The independent variable is an indicator for the
patient being admitted to a PE nursing home, instrumented by differences in distance to
the nearest PE and non-PE facility. Panel B presents results from a placebo analysis of
the relationship between private equity ownership and patient health and spending. For
this analysis, we use data over 2002–07, a period with very little actual PE ownership and
which has little overlap with the main analysis sample. We assign placebo PE acquisition
in 2004 to facilities that were eventually acquired before 2008 and 2005 to facilities
acquired in and post 2008 by PE firms. Accordingly we re-compute differential distance
values taking into account these placebo acquisitions. We present effects for claims-
based patient quality outcomes - patient death within 90 days of discharge from the
index stay, and total amount billed (2016$). All regressions include facility and patient
HRR x Year fixed effects, and patient risk controls. Patient risk controls include age,
race, gender, marital status, indicators for 17 pre-existing conditions used to compute
the Charlson Index, and an indicator if patients are dual eligible. Standard errors are
clustered by facility.
52Table 5: Heterogeneity in Patient Mortality
(1) (2) (3) (4)
Observations Mean Coefficient (Std. Errors)
A: Patient Level
1. Age & Risk
Low Risk, 65-80 2,052,655 0.08 0.0186* (0.011)
High Risk, 65-80 881,854 0.24 -0.0346* (0.021)
Low Risk, 80+ 3,326,940 0.16 0.0319*** (0.011)
High Risk, 80+ 1,104,387 0.29 0.023 (0.020)
2. Gender
Male 2,640,611 0.21 0.0105 (0.012)
Female 4,725,295 0.14 0.0210** (0.008)
3. Beneficiary Zip Income
Income < Median 3,681,687 0.18 0.0122 (0.010)
Income > Median 3,684,035 0.16 0.0262** (0.011)
4. Race
White 6,483,451 0.17 0.0206*** (0.008)
Other 881,923 0.16 -0.0219 (0.023)
5. Reason for hospitalization
Cardio-Vascular 1,340,956 0.20 0.0298* (0.016)
Injury 1,409,910 0.11 0.0236* (0.014)
Other 4,615,012 0.18 0.0096 (0.009)
B: Market Level
1. Hirfindahl Hirschman Index
HHI < Median 3,706,810 0.16 0.0223 (0.020)
HHI > Median 3,659,035 0.18 0.0144* (0.008)
Note: This table presents heterogeneity in the effects of PE ownership on patient mortality. Column
1 presents the sample size and Column 2 presents the mean. Columns 3 and 4 present the
corresponding coefficient β and its standard error obtained by estimating Equation (2) by 2SLS.
The independent variable is the indicator for a patient being admitted to a PE nursing home,
instrumented by differences in distance to the nearest non-PE and PE nursing home. The outcome
variable is an indicator for patient death within 90 days of discharge from the index stay. Panel A
explores heterogeneity on patient level factors - by dividing patients into 4 groups based on severity
of pre-existing co-morbidities (high risk= Charlson Index greater than 2) and age (greater than 80)
in row 1, gender in row 2, median income in the patient’s zipcode in row 3, race in 4, and the reason
for hospitalization prior to the nursing home stay in row 5. Panel B explores heterogeneity based on
market factors - dividing markets below and above the median Hirfindahl Hirschman Index (HHI).
We computed the HHI using market shares in terms of beds as observed in 2003-04, where the
HRR in which the nursing home is located is considered its market. All models include facility and
patient HRR x year fixed effects. We additionally control for the usual patient risk controls as in the
main regression. Standard errors are clustered by facility.
53Table 6: Patient wellbeing
(1) (2) (3) (4)
1(Starts Anti- 1(Mobility 1(Develops 1(Pain Intensity
Psychotics) Decreases) Ulcers) Increases)
1(PE) 0.0297*** 0.0425*** 0.0065 0.0273*
(0.006) (0.011) (0.008) (0.016)
Observations 7,365,934 7,365,934 7,365,934 7,365,934
Y-Mean 0.06 0.53 0.09 0.27
Note: This table presents estimates of the relationship between PE ownership and measures of patient
wellbeing obtained from clinical assessments. Each cell in the first row presents the coefficient β obtained
by estimating Equation (2). The independent variable is an indicator for the patient being admitted to a PE
nursing home, instrumented by differences in distance to the nearest PE and non-PE facility. All models
include facility and patient HRR x Year fixed effects. We additionally control for the usual patient risk controls
as in the main regression. The independent variable is an indicator for whether a nursing home is private
equity-owned (=1 if PE-owned, 0 otherwise) starting in the next year from the deal announcement date. We
present results for patient level outcomes - an indicator for patient starting anti- psychotics, decrease in patient
mobility, developing/worsening pressure ulcers, and increase in pain intensity. These variables take value one
if this condition is not flagged for the patient in the initial assessment, but is flagged at some point during the
stay. Standard errors are clustered by facility.
54Table 7: Patient-Level Analysis: Robustness
(1) (2) (3)
Mortality Log Amount Billed Log Amount Billed
(Stay + 90 Days) Per Patient Stay Per Patient Stay + 90 Days
1. Base Specification
1(PE) 0.0168** 0.1777*** 0.1054***
(0.007) (0.028) (0.024)
2. Chain Controls
1(PE) 0.0169** 0.1777*** 0.1055***
(0.007) (0.028) (0.024)
3. W/O Top 2 Deals
1(PE) 0.0309*** 0.2309*** 0.1429***
(0.011) (0.045) (0.037)
4. Top 5 Deals Only
1(PE) 0.0349*** 0.2469*** 0.1510***
(0.012) (0.046) (0.039)
5. Only For Profits
1(PE) 0.0138** 0.1474*** 0.0836***
(0.007) (0.026) (0.021)
6. Zip-Year Controls
1(PE) 0.0150** 0.1760*** 0.1029***
(0.007) (0.028) (0.024)
7. HSA-Year FEs
1(PE) 0.0211*** 0.1800*** 0.1130***
(0.008) (0.030) (0.025)
8. County-Year FEs
1(PE) 0.0221** 0.1430*** 0.0832***
(0.010) (0.034) (0.029)
9. No Controls
1(PE) 0.0296*** 0.2391*** 0.1131***
(0.008) (0.030) (0.024)
Observations 7,365,934 7,365,934 7,365,934
Y-Mean 0.17 9.07 9.57
Note: This table presents results from specification checks on the relationship between PE ownership and
patient health and spending. Each cell presents the coefficient βobtained by estimating Equation (2) by 2SLS.
The independent variable is an indicator for the patient being admitted to a PE nursing home, instrumented by
differences in distance to the nearest PE and non-PE facility. We present effects for patient death within 90
days of discharge from the index stay, the log of the total amount billed for the stay and the log of the amount
billed for the stay and across hospital inpatient, outpatient and nursing home over the 90 days following the
stay (2016$). All models include facility fixed effects. The first six rows include HRR x year fixed effects,
the seventh row uses Health Service Areas (HSA), and the eighth row uses county to define patient market
instead of HRR. The second row controls for facility being part of a chain. The third row calculates the results
excluding all data for chains involved in the 2 largest PE deals. The fourth row limits the PE group to only
the facilities bought in the 5 largest PE deals. The fifth row limits the sample only to for-profit facilities. The
sixth row includes patient zip controls: median household income, the shares of the population that are white,
that are renters rather than home-owners, that are below the federal poverty level, and that are enrolled in
Medicare Advantage program. The first eight rows includes patient risk controls: age, race, gender, marital
status, indicators for 17 pre-existing conditions used to compute the Charlson score, and an indicator if patients
are dual eligible. The ninth row presents coefficients from a model with fixed effects only. Standard errors are
clustered by facility.
55Table 8: Mechanisms and Operational Changes
A: Five Star Rating
(1) (2)
Deficiency Overall
Rating Rating
1(PE) -0.075** -0.079**
(No Control) (0.037) (0.036)
1(PE) -0.077** -0.082**
(With Control) (0.037) (0.036)
Observations 138,051 138,051
Y-Mean 2.9 3.2
B: Staff Per Patient Day
(1) (2) (3) (4)
All Staff Nurse Assistant Licensed Nurse Registered Nurse
1(PE) -0.050*** -0.068*** -0.019*** 0.037***
(No Control) (0.017) (0.010) (0.006) (0.005)
1(PE) -0.048*** -0.066*** -0.019*** 0.037***
(With Control) (0.016) (0.010) (0.006) (0.005)
Observations 283,767 283,767 283,767 283,767
Y-Mean 3.6 2.3 0.8 0.5
C: Log Financials
(1) (2) (3) (4)
Management Fee Building Lease Interest Expense Cash on Hand
1(PE) 0.074** 0.564*** 1.181*** -0.322***
(No Control) (0.032) (0.061) (0.096) (0.042)
1(PE) 0.074** 0.560*** 1.175*** -0.318***
(With Control) (0.032) (0.061) (0.096) (0.042)
Observations 231,556 231,584 231,613 231,569
Y-Mean 0.2 0.4 0.3 11.2
Note: This table presents estimates of the relationship between PE ownership and nursing home outcomes.
Each cell presents the coefficient β obtained by estimating equation 9 with a different outcome. The
independent variable is an indicator for whether a nursing home is PE-owned (=1 if PE-owned, 0 otherwise)
starting in the next year from the deal announcement date. Panel A presents results for quality outcomes
as measured by Five-star rating awarded by CMS - overall rating and deficiencies identified by independent
contractors in audits, respectively. A negative effect on ratings implies a decline in quality. Panel B presents
results on per patient nurse availability for all nurses, nurse assistants, licensed nurses, and registered nurses.
Panel C presents results on the log of management fees, building lease cost, interest expenses, and cash on
hand. The top row presents results with no controls. The bottom row presents the results including controls,
which consist of market-level and patient mix controls, as described in Section 6.1. All models include facility
and year fixed effects. All variables are winsorized at 1% and 99% levels. Standard errors are clustered by
facility.
56Appendix: For Online Publication
A Data appendix
This paper uses three primary data sources. We use (1) publicly available nursing home-
level data, (2) patient-level administrative claims data, both obtained from CMS, and (3)
Pitchbook data on PE deals. This section provides a detailed explanation of these data
sources and how we arrived at our analysis samples.
A.1 Nursing Home Data
Our data source on nursing home-level operations and performance is a compilation of
information obtained during annual surprise CMS inspector audits and data on nursing
home attributes and patient characteristics reported by the facilities themselves.33 The data
span 2000 through 2017. In each year we observe about 15,000 unique nursing homes, for
a total of approximately 280,000 observations. Of these, about 29,000 observations
represent facilities acquired by PE firms. The aggregate files provide annual data on basic
facility attributes, patient volume and case mix, nurse availability, and various components
of the Five Star ratings.34 These ratings started in 2009, so we cannot observe ratings
pre-buyout for deals before 2010. Fortunately, half of the PE deals in our sample,
accounting for 365 nursing homes, occurred post-2009.
Table 1 Panel A presents summary statistics on the Overall Five Star rating as well as the
other key nursing home-level variables used in the analysis. We first present the mean and
standard deviation for the whole sample (columns 1-2), then divide observations into two
groups—for facilities that are not PE-owned (columns 4-5) and for those that are (columns
6-7). We observe clear differences between PE-owned facilities and those not owned (all
statistically significant at the 1% level except where noted). PE targets are slightly larger,
have fewer staff hours per resident, and a lower Overall Five Star rating. There have been
secular increases for the whole sector in both ratings and staffing over time. For staffing, this
reflects more stringent standards from regulators over time. Average staff hours per patient
day increased from 3.5 in 2000 to 3.7 in 2017. Similarly, overall average Five Star ratings
increased from 2.9 in 2009 to 3.25 in 2017. As the PE deals occurred primarily later in the
sample, it is therefore remarkable that they have lower measures of quality on average.
A.2 Patient Data
Our second data source consists of patient-level billing claims and assessment data for
Medicare fee-for-service beneficiaries from 2004 to 2016. We observe the universe of
billing data for hospital care (inpatient and outpatient) and nursing homes for these
beneficiaries, as well as detailed patient assessments recorded in the Minimum Data Set
(MDS).35 We use these files to track beneficiaries’ demographics, spending, and health
33These files were organized and made available for research by the Long Term Care Focus research center
at Brown University. See www.ltcfocus.org for more details.
34For more details on how the ratings are produced, see Rating Guide.
35Specifically, we use 100% samples of the following: Medicare Beneficiary Summary File (MBSF),
Hospital inpatient and outpatient, and Skilled Nursing Facility claims files. These were obtained through a
reuse DUA with CMS and accessed through the NBER.
57outcomes such as mortality. The MDS helps observe clinical assessments such as mobility
and the use of antipsychotic drugs.
The unit of observation is a nursing home stay for a Medicare beneficiary that begins
during our sample period, which we begin in 2005 in order to have at least one look-back
year. Our main sample restriction is to identify index nursing home stays for patients,
defined as stays that begin at least a year after discharge from a previous nursing home stay.
This helps avoid mis-attributing adverse effects to the wrong nursing home. To further
avoid attribution error, we consider only the patient’s first index stay in our entire sample
period. Hence, each patient appears only once in our sample. Using this approach, we settle
on a sample of more than seven million patients over 12 years. For each of these patients,
we also observe clinical assessments from the MDS, which we successfully match to the
claims files. Following the prior literature (Grabowski, Feng, Hirth, Rahman and Mor,
2013), we use some other restrictions to arrive at our sample. We restrict to patients over 65
years of age who are enrolled in Medicare parts A and B for at least 12 months before the
start of the nursing home stay. This restriction ensures that we observe prior medical care
history and pre-existing conditions. We also restrict to stays associated with a hospital visit
in the previous month, so that all patients are admitted after a hospital-based procedure and
are relatively homogeneous. We drop patients who went to a nursing home in a state other
than their state of residence as recorded in the Medicare master beneficiary summary file.
This drops a small fraction of patients (less than 5%) and is meant to exclude patients who
may be traveling when admitted to a nursing home. We match the index nursing home
stays to the MDS sample on beneficiary ID, facility ID, and admission date. We achieve a
match rate of 94% and drop unmatched patients. We drop facilities with fewer than 100
patients over the entire sample period to avoid special facilities and mitigate noise.
Table 1 Panel B presents summary statistics on the final patient-level sample. We use an
indicator for death within 90 days following discharge (including during the stay), based on
death dates recorded in the Medicare master beneficiary summary file. We use two measures
of spending. The first is the total amount that the nursing home bills to Medicare and the
patient for the index stay in 2016 dollars. Medicare covers the entire cost until the 21st day
of stay, at which point the patient begins paying a coinsurance, which has risen somewhat
over time and is now $170.5 per day.36 In our data, about 90% of total payments are by
Medicare. PE-owned facilities charge about 10% more than other facilities. The second
measure is the total amount paid for the stay and the 90 days following discharge. This
captures any subsequent hospital inpatient or outpatient care, and it provides a more holistic
picture of patient care.
Demographic measures associated with risk are quite similar across the types of
facilities, including patient age, the share of patients who are black and married, and the
Charlson Comorbidity Index, a standard measure of patient mortality risk based on
co-morbidities (Charlson, Szatrowski, Peterson and Gold, 1994).37 We create a high-risk
indicator that is one if the previous-quarter Charlson score is greater than two. According
to this definition, about 30% of patients are high-risk. The difference between facility types
is not significant.
Finally, we examine four measures of patient well-being which comprise inputs to the
36See https://www.resdac.org/cms-data/files/ip-ffs/data-documentation and
https://www.medicare.gov/Pubs/pdf/10153-Medicare-Skilled-Nursing-Facility-Care.pdf.
37The “Charlson score" assigns a point score to each of 17 disease categories recorded during the 3 months
before the index stay and sums them to create an overall disease burden score.
58quality portion of CMS’ Five Star ratings. The first is an indicator for the patient starting
antipsychotic medication during the stay. The second is an indicator for the patient’s self-
reported mobility score declining during the stay. The third is an indicator for developing a
pressure ulcer. The fourth is an indicator for the patient’s self-reported pain intensity score
increasing during the stay.
A.3 PE Deal Data
Our primary source of data on PE transactions is a proprietary list of deals in the “Elder
and disabled care” sector compiled by Pitchbook Inc., a leading market intelligence firm in
this space. The deals span 2004 to 2015. We match the target names to individual nursing
facilities using name (facility or corporate owner) and address as recorded in CMS data.38
Target names in these deals typically refer to holding companies, which often do not reflect
the names of individual facilities. The matching process required manual Internet searches
to confirm chain affiliations. We supplement the Pitchbook data in two ways. First, we
conduct additional Internet searches that yielded a small number of PE deals not reported by
Pitchbook. Second, we obtain a list of merger and acquisition deals from 2005 to 2016 from
Levin Associates, a market intelligence firm that tracks the healthcare sector. This helps us
to identify facilities that did not experience a new PE deal, but were acquired by an existing
PE-owned chain.39
This process yielded 128 deals, which correspond to a change in ownership to PE for
1,674 facilities. The deals are spread over time (no particular year or part of the business
cycle dominates) and across PE firms. Figure B.1 shows the number of deals in each year.
In total, our data contain 136 unique PE firms that acquired nursing homes. Most deals are
syndicated and involve multiple PE firms. Table B.1 presents the top 10 deals by number
of facilities acquired. Deal sizes are skewed, with the top 10 deals accounting for about
80% of all facilities acquired. On average, we observe PE-owned facilities for eight years
post-acquisition.40
It is difficult to ascertain whether we comprehensively capture PE activity in this sector.
While there is no ‘official’ tally of PE-owned nursing homes to benchmark against, our
sample size compares favorably against an estimate of 1,876 nursing homes reportedly
acquired by PE firms over a similar duration, 1998–2008 (GAO, 2010). Nonetheless, our
analysis likely underestimates the extent of PE activity in nursing homes, as matching
between Pitchbook deals and individual facilities is very challenging.
To understand whether deals are concentrated in particular regions, we plot the location
of PE-owned facilities across the U.S. in Figure B.2. PE firms appear to be more active in
large metropolitan markets, and in certain states such as Florida, Texas, New York,
Pennsylvania and Massachusetts. However, there is no obvious concentration, and we do
not find systematic variation with local measures of income, age, elder population, or share
38We obtain data on nursing home attributes (name, address, city, owner name and type, number of beds) and
quality measures (deficiencies) from Nursing Home Compare. See https://data.medicare.gov/data/
nursing-home-compare for more details.
39We matched approximately 290 additional facilities using information from the Levin files to the CMS
data. Of these, about 40 were PE-owned.
40A likely source of measurement error is not capturing PE disinvestment from facility ownership. For the
top 10 deals (80% of facilities) we verified PE exit via manual internet searches and incorporated it in the
analysis. The main results are robust to dropping observations of facilities that have been owned by PEs for 10
years or more. As expected, the coefficients modestly increase in magnitude when we do so.
59of patients eligible for Medicare Advantage.
A.4 Targeting
This paper does not address why nursing homes may or may not be profitable acquisition
targets, and does not assess returns from investing. However, exploring what types of
facilities are targeted can help to interpret the effects of buyouts on patient welfare and is
also useful for identifying the most relevant control variables for our empirical analysis.
We describe which characteristics are robustly associated with buyouts in Table A.1, which
presents estimates of Equation (11):
PE j,t = αs + αt + X′
j,t β+ ϵj,t (11)
Here, PE j,t is set to 100 if the facility j is acquired in a PE deal in year t (we drop all
years post-deal, and multiply by 100 for ease of reading). PEj,t is zero for never-PE and
PE-owned facilities before the deal. We include state and year fixed effects.
We report models including variables known to be central to nursing home quality of care
and economics or that are potentially important and robustly predict buyouts. In column 1,
we find that facilities in more urban counties are more likely to be targeted.41 Urban nursing
homes tend to be closer to hospitals and likely enjoy thicker labor markets. Facilities in a
state with a higher ratio of elderly people are also more likely to be targeted. County-level
income, race, and home ownership do not predict buyouts. Results for these covariates are
not presented.
In column 2, we turn to facility characteristics. Chains are more likely to be acquired
than independent facilities, likely reflecting substantial fixed costs in deal-making. Hospital-
owned facilities are less likely to be targeted. PE firms also tend to target larger and higher-
occupancy facilities. We consider patient-level characteristics in column 3: the share of
the nursing home’s patients covered by Medicaid, the share on private insurance, and the
share who are Black. The first two are strongly negatively associated with buyouts, meaning
that a higher share of Medicare patients (the omitted group) is positively associated with
being targeted. In column 4, we assess two facility-level quality measures we employ in
the analysis: Five Star overall rating and staff hours per patient day. Both are negatively
associated with buyouts, but once we control for rating, staffing is not significant. These
results indicate that PE firms target relatively low-performing nursing homes.
Finally, in column 5 we include simultaneously all of the variables from the previous
models that had predictive power. Some, such as admits per bed and hospital ownership,
become small and insignificant after controlling for the other variables. Notably, the state
elder ratio, chain indicator, and Five star rating retain their magnitudes and precision.
41We define urban as being in the top 2 out of 9 county groups classified as urban based on a Department of
Housing and Urban Development 2003 rural-urban classification.
60Table A.1: Targeting
Mean (1) (2) (3) (4) (5)
Urban Indicator 0.56 0.193*** 0.105**
(0.037) (0.041)
State Elder Ratio 0.24 4.340*** 18.819***
(1.328) (3.906)
1(Chain) 0.53 0.835*** 0.367***
(0.033) (0.029)
Hospital-Owned 0.07 -0.221*** -0.003
(0.053) (0.067)
Log(Beds) 4.5 0.287*** 0.086***
(0.030) (0.032)
Admits Per Bed 2.08 0.051*** 0.009
(0.007) (0.015)
Ratio Medicaid 0.60 -0.879*** -0.434*
(0.117) (0.229)
Ratio Private 0.25 -1.441*** -0.422*
(0.144) (0.236)
Ratio Black 0.10 0.002
(0.099)
Overall Rating 3.15 -0.075*** -0.066***
(0.015) (0.015)
Staff Hr per Patient Day 3.55 -0.022
(0.018)
Observations Y-Mean (pp) 235,670 218,592 218,592 103,831 103,831
0.6 0.6 0.6 0.6 0.6
Note: This table shows estimates of the relationship between pre-existing nursing home characteristics and
whether a nursing home is a target of a PE buyout. Column 1 presents market-level attributes: an indicator for
urban and the share of state population which is elderly. Column 2 presents facility-level attributes: indicator
for being member of a chain, indicator for the nursing home being hospital-based, the log number of beds,
and admits per bed. Column 3 presents patient mix controls: share of patients covered by Medicaid, share of
patients who pay privately, and the share of patients who are black. Column 4 presents quality metrics such
as Five-star ratings awarded by CMS and staff hours per patient day. We re-run the regression on all variables
which appear significant in Columns 1 to 4 in Column 5. The dependent variable is 100 if the nursing home
was acquired by PE in that year and 0 otherwise. We remove all observations of private equity-owned facilities
in years following the take-over by PE. We control for state and year FEs. Standard errors are clustered by
facility.
61B Supplementary Figures and Tables
Figure B.1: PE deals for Nursing Homes by Year
Note: This figure presents the number of unique deals for active nursing homes by PE firms for each year over
the period 2004–2015.
62Figure B.2: Location of Private Equity Targets
63
Note: This figure presents the number of facilities bought by PE firms in each county over the period 2004–
2015. We identified 1,674 such facilities.Figure B.3: Initial Patient Assesments
A: Dementia B: Alzheimers
C: Hip Fracture D: Urinary Tract Infection
Note: This figure presents event studies on initial patient assessments around the time a nursing home
experiences a PE buyout. To match the event study plots presented in the main text, we estimate these models
on collapsed facility-year level data and use the same specification, i.e., facility and year fixed effects, patient
mix, and market controls, as described in Section 6.1. Each point in the figures represents the coefficient
βs obtained by estimating Equation (10) as discussed in Section 6. Year= -2 is the omitted point. Panel A
presents results on the share of patients diagnosed with Dementia, Panel B on Alzheimers, Panel C on Hip
Fractures, and Panel D on Urinary Tract Infections, respectively, at admission to the index nursing home stay.
Standard errors are clustered by facility.
64Figure B.4: Patient distance to Nursing Home
A: CDF: All Patients B: CDF: PE vs. Non-PE Patients
C: Trendline: Share going to Closest Nursing Home D: Event Study: PE Acquisition
Note: This figure provides descriptes on patient zip code distance to index nursing home zip code. Panels A
and B present CDFs of the distance from patient zip code to index nursing home zip code. Panel A presents the
CDF pooling PE and non-PE patients together. It also identifies the median, 75th and 90th percentile values.
Panel B presents the CDFs separately for PE and non-PE patients, and their respective median values. Panel
C presents the annual trendline for the share of patients going to their closest nursing home. Panel D presents
the event study of the mean patient distance around a PE acquisition. Each point in the figure represents the
coefficient βs obtained by estimating Equation (10) as discussed in Section 6. Year= -2 is the omitted point.
The model includes facility and HRR x year fixed effects, patient mix, and market controls. Standard errors
are clustered by facility.
65Figure B.5: Patient Outcome Measures
A: Mortality (Stay + 90 Days) B: Log Amount Billed (Patient Stay + 90 Days)
C: 1(Starts Antipsychotic Medications) D: 1(Mobility Decreases)
E: 1(Develops Ulcers) F: 1(Pain Intensity Increases)
Note: This figure presents event studies on patient outcome measures around the time a nursing home
experiences a PE buyout. To match the event study plots presented in the main text, we estimate these models
on collapsed facility-year level data and use the same specification, i.e., facility and year fixed effects, patient
mix, and market controls, as described in Section 6.1. Each point in the figures represents the coefficient βs
obtained by estimating Equation (10) as discussed in Section 6. Year= -2 is the omitted point. Panels A and
B present results on the share of patients dying within 90 days of discharge from the index stay, and total
amount billed over the 90-day episode including the index stay (2016$). Panels C to F present results for
MDS assessment based outcomes - the facility level mean for indicators for patient starting antipyschotics,
decrease in patient mobility, developing/worsening pressure ulcers, and increase in pain intensity respectively.
Spending is winsorized at the 1% and 99% level. Standard errors are clustered by facility.
66Figure B.6: MTE: Additional figures
A: Common Support
MTE
0.06
0.05
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Unobserved resistance to treatment
Baseline 3rd order 4th order 5th order
B: Order of polynomial
Note: This figure presents additional plots pertaining to Marginal Treatment Effects (MTE) analysis using
the Medicare patient-level data. Panel A presents the overlap in distributions of PE and non-PE groups by
propensity score, using a linear scale for the Y-axis. Panel B demonstrates robustness of the slope of the MTE
curve to using different orders of polynomials. Section 5.2.2 presents details of the MTE estimation.
67Figure B.7: Staff Availability and Five Star Ratings
A: Overall Rating
B: Deficiency Rating
Note: This figure presents scatter plots of changes in total staff hours available per patient day in the three years
post-PE buyout versus three years pre-buyout on the X-axis, against changes in CMS Five-star rating over the
same period on the Y-axis. Panel A presents overall rating, and Panel B presents survey based deficiency
ratings. The data was collapsed into 20 equal sized bins and we plot the means in each bin. The figures also
present fitted lines for these plots obtained using linear regressions on the underlying data. Each plot also
presents the slope coefficient with standard error.
68Figure B.8: Patient Volume
A: Log Beds - Facility B: Log Admissions - Facility
C: Log Admissions - Market (HRR)
Note: This figure presents event studies on facility characteristics around the time a nursing home experiences
a PE buyout. Each point in the figures represents the coefficient βs obtained by estimating Equation (10) as
discussed in Section 6. Year= -2 is the omitted point. Panels A and B present results on the log of beds and
admissions at the facility level, and Panel C on log admissions at the market level (HRR). All models – except
when studying market-level volume – include facility and year fixed effects, patient mix, and market controls,
as described in Section 6.1. All dependent variables are winsorized at 1% and 99% levels. Standard errors are
clustered by facility.
69Table B.1: Top 10 Private Equity Deals
Sr. Target Private Equity Deal Number of
No. Name Firm(s) Year Facilities
1 Genesis Healthcare Formation Capital, JER Partners 2007–15 327
2 Golden Living Fillmore Capital Partners 2006 321
3 Kindred Healthcare Signature Healthcare, Hillview Capital 2014 150
4 HCR Manorcare Stockwell Capital, The Carlyle Group 2007–18 145
5 Mariner Healthcare Fillmore Capital Partners 2004 95
6 Skilled Healthcare Group Onex, Heritage Partners 2005–07 76
7 Trilogy Investors Lydian Capital Partners 2007–15 65
8 Lavie Care Centers Formation Capital, Senior Care Development 2011 61
9 Laurel Health Care Company Formation Capital, Longwing Real Estate Ventures 2006–16 41
10 Harden Healthcare NXT Capital, Oaktree Speciality Lending 2013 35
Note: This table presents some details on the top 10 PE deals in our sample, ordered by the number of unique
nursing home facilities involved in the deal. This represents the number of facilities we were able to identify
and match in our administrative data, the actual number of facilities in the deal may have been different. We
set the PE indicator to turn on in the year following the deal year. If a closing year is mentioned, it implies the
PE investors exited or went public in that year. Accordingly, we turn off the PE indicator in the closing year.
70Table B.2: Complier Characteristics
Observations Coefficient (Std. Errors) Ratio
Full Sample 7,365,934 -0.0445*** (0.003)
A. Age & Risk
Low Risk, 65-80 2,052,655 -0.0405*** (0.002) 0.91
High Risk, 65-80 881,854 -0.0471*** (0.003) 1.06
Low Risk, 80+ 3,326,940 -0.0451*** (0.003) 1.01
High Risk, 80+ 1,104,387 -0.0478*** (0.003) 1.07
B. Gender
Male 2,640,611 -0.0456*** (0.003) 1.02
Female 4,725,295 -0.0439*** (0.003) 0.99
C. Marital Status
Unmarried 4,838,365 -0.0446*** (0.003) 1.00
Married 2,527,548 -0.0439*** (0.003) 0.99
D. Beneficiary Zip Income
Income < Median 3,681,687 -0.0554*** (0.004) 1.24
Income > Median 3,684,035 -0.0353*** (0.003) 0.79
E. Race
White 6,483,451 -0.0451*** (0.003) 1.01
Other 881,923 -0.0380*** (0.003) 0.85
Note: This table presents first stage equivalent estimates of the 2SLS for various patient
subsamples. We present the coefficient β, obtained by estimating the equation PEi =
αj + αm,t + β1(DDi > Median) + ϵi. 1(DDi > Median) is an indicator for patient
i’s differential distance to the nearest PE-owned facility being greater than the median
value. The model includes facility j and patient HRR x year fixed effects, but no other
controls. We divide the sample by age and risk, gender, marital status, income in patient
zip code, and race. Details are available in Section 4.2. We also present the ratio of the
coefficient obtained for each subsample to that for the full sample. Standard errors are
clustered by facilities.
71Table B.3: Mortality Effects by Duration
(1) (2) (3) (4)
(Stay + 30 Days) (Stay + 60 Days) (Stay + 90 Days) (Stay + 365 Days)
1(PE) 0.009 0.0148** 0.0169** 0.0239***
(0.006) (0.007) (0.007) (0.008)
Observations 7,365,934 7,365,934 7,365,934 7,365,934
Y-Mean 0.12 0.15 0.17 0.24
F-Stat 223.9 223.9 223.9 223.9
Coefficient/ Y-Mean 8% 10% 10% 10%
Note: This table presents estimates of the relationship between PE ownership and patient mortality. Each
cell presents the coefficient β obtained by estimating Equation (2) by 2SLS. The independent variable is an
indicator for the patient being admitted to a PE nursing home, instrumented by differences in distance to
the nearest PE and non-PE facility. We present effects for mortality at different durations - patient death
within 30, 60, 90, and 365 days of discharge from the index stay. All regressions include facility and patient
HRR x year fixed effects, and patient risk controls. Patient risk controls include age, race, gender, marital
status, indicators for 17 pre-existing conditions used to compute the Charlson Index, and an indicator for dual
eligibility. Standard errors are clustered by facility.
72Table B.4: Mortality Costs
(1) (2)
Male Female
A: IV estimates
1(PE) 0.0105 0.0210**
(0.012) (0.008)
Observations 2,640,611 4,725,295
Y-Mean 0.21 0.14
F-Stat 221 221
B: Placebo
1(PE) 0.0091 0.0044
(0.006) (0.005)
Observations 2,497,830 4,661,700
Y-Mean 0.23 0.15
F-Stat 431 440
C: Calculations
Number of Patients in PE Facilities 435,035 741,838
Additional Deaths 4,568 15,579
Total Lives Lost 20,146
Mean Life Expectancy 6.7 8.2
Additional Loss in Person Years 30,814 128,384
Total Person Years Lost 159,198
Value of Life Year (2016 $) 130,000
Total Cost (2016 $) 20.7 Billion
Note: This table presents estimates of additional deaths, life-years lost, and the
associated cost using standard estimates of statistical value of a life-year due to PE
ownership of nursing homes. Panel A presents the coefficient βobtained by estimating
Equation (2) by 2SLS. The independent variable is the indicator for a patient being
admitted to a PE nursing home, instrumented by differences in distance to the nearest
non-PE and PE nursing home. The outcome variable is an indicator for patient death
within 90 days of discharge from the index stay. Panel B presents a placebo analysis for
this patient subsample using the same approach as for the whole sample, as presented
in Table 4. All models include facility and patient HRR x year fixed effects and the
usual patient risk controls as in the main specification. Standard errors are clustered by
facility. Panel C presents calculations to estimate lives, life-years lost and total cost based
on Panel A coefficients. We calculate average life expectancy at discharge (by gender)
using the observed distribution of lifespans for Medicare patients. For patients still alive
at the end of our sample, we assign a year of death based on patient gender and age
using Social Security actuary tables. We adjust downward the resulting life expectancy
to account for the fact the decedents tend to be older than the average nursing home
patient (about two years).
73Table B.5: Patient-Level Analysis: OLS Results
A: Initial Patient Assesments
(1) (2) (3) (4)
Dementia Alzheimers Hip Fracture Urinary Tract Infec.
At Admission At Admission At Admission At Admission
1(PE) -0.0098*** -0.0040*** -0.0034*** 0.0044**
(0.002) (0.001) (0.001) (0.002)
Observations 7,365,934 7,365,934 7,365,934 7,365,934
Y-Mean 0.16 0.05 0.09 0.16
B: Main Outcomes
(1) (2) (3)
Mortality Log Amount Billed Log Amount Billed
(Stay + 90 Days) Per Patient Stay Per Patient Stay + 90 Days
1(PE) 0.0034*** -0.0221*** -0.0118**
(0.001) (0.006) (0.005)
Observations 7,365,934 7,365,934 7,365,934
Y-Mean 0.17 9.07 9.57
C: Assesment Based Outcomes
(1) (2) (3) (4)
1(Starts Anti- 1(Mobility 1(Develops 1(Pain Intensity
Psychotics) Decreases) Ulcers) Increases)
1(PE) 0.0115*** 0.0349*** 0.0094*** 0.0266***
(0.001) (0.003) (0.003) (0.005)
Observations 7,365,934 7,365,934 7,365,934 7,365,934
Y-Mean 0.06 0.53 0.09 0.27
Note: This table presents OLS estimates of the relationship between PE ownership and patient health and
spending. Each cell presents the coefficient βobtained by estimating Equation (2) by OLS. The independent
variable is an indicator for the patient being admitted to a PE nursing home. In Panel A, we present effects for
initial patient assessments - dementia, alzheimers, hip fracture and urinary tract infection at time of admission.
In Panel B, we present effects on patient death within 90 days of discharge from the index stay and total
amount billed during the stay and during the 90 day episode (2016$). Panel C presents results for assessment
based outcomes recorded in the MDS - an indicator for patient starting antipyschotics, decrease in patient
mobility, developing/worsening pressure ulcers, and increase in pain intensity. All regressions include facility
and patient HRR x Year fixed effects, and patient risk controls. Patient risk controls include age, race, gender,
marital status, indicators for 17 pre-existing conditions used to compute the Charlson Index, and an indicator
for dual eligibility. Standard errors are clustered by facility.
74Table B.6: Robustness: Facility-Level Outcomes
A: Five Star Rating
(1) (2)
Deficiency Overall
Rating Rating
1. Chain Controls
1(PE) -0.074** -0.079**
(0.036) (0.028)
2. W/O Top 2 Deals
1(PE) -0.145*** -0.204***
(0.050) (0.042)
3. Only For Profit
1(PE) -0.077** -0.082**
(0.036) (0.028)
Observations 138,051 138,051
Y-Mean 2.9 3.2
B: Staff Per Patient Day
(1) (2) (3) (4)
All Staff Nurse Assistant Licensed Nurse Registered Nurse
1. Chain Controls
1(PE) -0.050*** -0.068*** -0.019*** 0.037***
(0.016) (0.010) (0.006) (0.005)
2. W/O Top 2 Deals
1(PE) -0.100*** -0.101*** -0.021** 0.030***
(0.026) (0.015) (0.009) (0.008)
3. Only For Profit
1(PE) -0.045*** -0.062*** -0.024*** 0.039***
(0.017) (0.010) (0.006) (0.005)
Observations 283,767 283,767 283,767 283,767
Y-Mean 3.6 2.3 0.8 0.5
C: Log Financials
(1) (2) (3) (4)
Management Fee Building Lease Interest Expense Cash on Hand
1. Chain Controls
1(PE) 0.074** 0.564*** 1.181*** -0.321***
(0.032) (0.061) (0.096) (0.042)
2. W/O Top 2 Deals
1(PE) 0.042 0.809*** 2.048*** -0.366***
(0.050) (0.102) (0.160) (0.068)
3. Only For Profit
1(PE) 0.056* 0.570*** 1.179*** -0.289***
(0.032) (0.061) (0.096) (0.043)
Observations 231,556 231,584 231,613 231,569
Y-Mean 0.2 0.4 0.3 11.2
Note: This table presents robustness tests on the estimates of the relationship between PE buyouts and Five
star ratings, nurse availability, and financials. The corresponding main results are presented Table 8. Each
cell presents the coefficient βobtained by estimating Equation (9) with a different outcome. The independent
variable is an indicator for whether a nursing home is PE-owned (=1 if PE-owned, 0 otherwise) starting in the
next year from the deal announcement date. We control for a chain indicator in the first row, remove the top 2
deals by size in the second row, and estimate the results on a sample limited to for-profit facilities in the third
row. We do not present results limiting to the Top 5 deals as Five Star ratings are only available post-2009,
and 4 Top 5 deals occurred before 2009. All models include facility and year fixed effects. All variables are
winsorized at 1% and 99% levels. Standard errors are clustered by facility.
75Table B.7: Patient Volume
Facility Level Market Level
(1) (2) (3)
Log Log Log
Beds Admissions Admissions
1(PE) -0.002 0.036*** 0.014
(No Control) (0.003) (0.009) (0.014)
1(PE) -0.003 0.035*** 0.007
(With Control) (0.003) (0.009) (0.011)
Observations 283,767 283,767 5,364
Y-Mean 4.5 4.8 12.7
Note: This table presents estimates of the relationship between PE ownership and patient volume. Each cell
presents the coefficient β obtained by estimating Equation (9) with a different outcome. The independent
variable is an indicator for whether a nursing home is PE-owned (=1 if PE-owned, 0 otherwise) starting in
the next year from the deal announcement date. We present results on the log number of beds, log number
of admissions in facility, and log number of admissions at HRR level. The bottom row presents the results
including controls, which consist of market-level and patient mix controls, as described in Section 6.1. All
models include facility and year fixed effects. All variables are winsorized at 1% and 99% levels. Standard
errors are clustered by facility.
76
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