The Effects of Bundled Payment Programs for Hip and Knee Arthroplasty on Patient-Reported Outcomes

Journal Pre-proof The Effects of Bundled Payment Programs for Hip and Knee Arthroplasty on PatientReported Outcomes Daniel J. Finch, BA, Vincent D. Pellegrini, MD, Patricia D. Franklin, MD, MBA, MPH, Laurence S. Magder, PhD, Christopher E. Pelt, Brook I. Martin, PhD, MPH, The PEPPER Investigators PII:

S0883-5403(19)31100-3

DOI:

https://doi.org/10.1016/j.arth.2019.11.028

Reference:

YARTH 57645

To appear in:

The Journal of Arthroplasty

Received Date: 1 August 2019 Revised Date:

10 November 2019

Accepted Date: 17 November 2019

Please cite this article as: Finch DJ, Pellegrini VD, Franklin PD, Magder LS, Pelt CE, Martin BI, The PEPPER Investigators, The Effects of Bundled Payment Programs for Hip and Knee Arthroplasty on Patient-Reported Outcomes, The Journal of Arthroplasty (2019), doi: https://doi.org/10.1016/ j.arth.2019.11.028. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Elsevier Inc. All rights reserved.

The Effects of Bundled Payment Programs for Hip and Knee Arthroplasty on Patient-Reported Outcomes

Authors: Daniel J. Finch,1,2 BA; Vincent D. Pellegrini,3 MD Patricia D. Franklin,4 MD, MBA, MPH; Laurence S. Magder,5 PhD; Christopher E. Pelt,6 Brook I. Martin,6 PhD, MPH; The PEPPER Investigators

Author Information: 1: Department of Orthopaedics, University of Utah School of Medicine, Salt Lake City, UT, USA Electronic Address: [email protected] Physical Address: University of Utah Orthopaedic Center, 590 Wakara Way, Salt Lake City, UT, 84108 2: Tufts University School of Medicine, Boston, MA, USA 3: Department of Orthopaedics, Geisel School of Medicine, Hanover, NH, USA. 4: Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA 5: Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, USA 6: Department of Orthopaedics, University of Utah School of Medicine, Salt Lake City, UT, USA

1

The Effects of Bundled Payment Programs for Hip and Knee Arthroplasty

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on Patient-Reported Outcomes

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1

4 5

Abstract: Background: Patient-reported outcomes are essential to demonstrate the value of hip and knee

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arthroplasty, a common target for payment reforms. We compare patient-reported global and

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condition-specific outcomes after hip and knee arthroplasty based on hospital participation in

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Medicare’s bundled payment programs.

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Methods: We performed a prospective observational study using the Pulmonary Embolism

10

Prevention after Hip and Knee Replacement trial. Differences in patient-reported outcomes through six

11

months were compared between bundle and non-bundle hospitals using mixed-effects regression,

12

controlling for baseline patient characteristics. Outcomes were the brief Hip or Knee Osteoarthritis

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Outcomes Survey (HOOS JR. or KOOS JR.), the Patient-Reported Outcomes Measurement Information

14

System Physical Health Score (PROMIS-PH), and the Numeric Pain Rating Scale (NPRS), measures of joint

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function, overall health, and pain, respectively.

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Results: Relative to non-bundled hospitals, arthroplasty patients at bundled hospitals had

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slightly lower improvement in KOOS JR. (-1.8 point relative difference at six months; 95%CI -3.2, -0.4;

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p=0.011) and HOOS JR. (-2.3 point relative difference at six months; 95%CI -4.0, -0.5; p=0.010). However,

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these effects were small and the proportions of patients who achieved a minimum clinically important

20

difference (MCID) were similar. Pre- to postoperative change in PROMIS-PH and NPRS demonstrated a

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similar pattern of slightly worse outcomes at bundled hospitals with similar rates of achieving a MCID.

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Conclusions: Patients receiving care at hospitals participating in Medicare’s bundled payment

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programs do not have meaningfully worse improvements in patient-reported measures of function,

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health, or pain after hip or knee arthroplasty.

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Keywords: Patient-reported Outcomes, Bundled Payments, Total Knee Arthroplasty, Total Hip

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Arthroplasty, KOOS, HOOS

2

27

Body:

28

Background:

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Bundled payments for lower extremity joint replacement (LEJR) have reduced Medicare

30

spending, but their impact on patient function and pain is understudied. [1-4] Under bundled payments,

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hospitals might have perverse incentives to skimp on needed or recommended care, [5] select healthier

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cases, [6,7] and inflate diagnosis and treatment volume, [8] which could compromise patient

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improvement. Thus, despite cost savings, assessing value (defined as outcomes/costs [9]) of bundled

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payments requires knowledge of patient-reported outcomes (PROs). [10] We prospectively compared

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patient-reported outcomes following hip and knee arthroplasty based on hospital participation in

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Medicare’s bundled payment programs.

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Bundled payments are a predetermined reimbursement for services related to a condition or

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procedure over a defined timeframe. [11] They intend to incentivize coordinated care and reduce

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overutilization by offering shared savings if actual costs are below the predetermined rate. [2,12] The

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Center for Medicare and Medicaid Innovation (CMMI) introduced the Bundled Payment for Care

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Improvement (BPCI) program in 2013 to transition toward alternative payment models. [11,13] The

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models targeted 48 clinical episodes, including LEJR. Through the voluntary BPCI, Medicare spending for

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LEJR declined, [3,14-17] prompting the mandatory Comprehensive Care for Joint Replacement program

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(CJR) in 2015. CJR started as a 5-year model for all hospitals within randomly-selected metropolitan

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statistical areas (MSAs) with a population exceeding 50,000, excluding BPCI hospitals. [18] It increased

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the number of hospitals participating in bundled payments, phased in regional pricing targets, and

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expanded rural and small-volume hospital participation. More recent changes curtailed the number of

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mandatory MSAs and exempted some small volume and rural hospitals. [19] The CJR program also

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demonstrated savings for Medicare, [4] mostly by reducing post-acute care spending. Participation in

3

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either BPCI or CJR is not associated with changes in procedure volume, patient composition,

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complication, patient satisfaction, emergency admits, or readmission. [1,4,20]

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While previous reports [1,3,4,14,21] have examined the effects of bundled payments on costs,

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readmission, discharge disposition, reoperation, and emergency department utilization, their effects on

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patient-reported pain and function is limited to single institutions [22,23] and recall surveys. [14] We

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sought to compare patient-reported function, general health, and pain following LEJR between bundle

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and non-bundle hospitals in patients enrolled in a prospective, multicenter clinical trial.

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Methods:

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Setting:

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Patient-reported outcomes were collected through the Comparative Effectiveness of Pulmonary

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Embolism Prevention after Hip and Knee Replacement (PEPPER) trial, a pragmatic, multicenter

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randomized trial evaluating safety and effectiveness of antithrombotic drugs. [24] PEPPER

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(ClinicalTrials.gov NCT02810704) enrolls subjects from 27 hospitals. While the antithrombotic safety

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focus was unrelated to our analysis, PEPPER provided a natural experiment to assess PRO’s from

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multiple hospitals. We excluded a Canadian site not subject to Medicare reimbursement. Hospitals were

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classified as either “bundle” or “non-bundle” based on their participation in either of CMMI’s LEJR

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bundled payment programs (BPCI or CJR), confirmed in publicly available files. [11,18]

68 69 70

Participants: Participants enrolled in PEPPER between 12/12/2016 and 04/30/2019 who completed baseline

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surveys and had undergone elective primary or revision total knee arthroplasty (TKA) or total hip

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arthroplasty (THA) were included in our analysis (Figure 1). Patients with comorbidities that confound

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the assessment of antithrombotic medications were excluded (Appendix 1).

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74 75 76

Outcomes: Validated outcomes for function, global health, and pain were reported by patients pre-

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operatively (baseline), and at one, three, and six months postoperatively. For TKA, we ascertained the

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brief Knee Osteoarthritis Outcomes Survey (KOOS JR.), which includes seven items related to stiffness,

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pain, function, and daily living. [25] Similarly, the brief Hip Osteoarthritis Outcomes Survey (HOOS JR.)

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asks six items concerning hip pain, function, and daily living. [26] Both the KOOS JR. and HOOS JR. are

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scored on a 0-100 scale with a higher score indicating improved function. [25,26] Minimum clinically

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important difference (MCID) reflects the minimum difference that a patient perceives as a change in

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health. [27] Using an anchor-based approach, 7 points is the smallest estimate of MCID for KOOS JR. and

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HOOS JR, [27] although estimates of MCID vary. [28]

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Global health was measured using the Patient-Reported Outcomes Measurement Information

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System (PROMIS-PH), and the Numeric Pain Rating Scale (NPRS), a measure of general pain. The

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PROMIS-PH is evaluated using a T-score set at a mean of 50, with greater scores representing improved

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general health, and a MCID of 7.9 points. [28,29] The NPRS is scored from 0 to 10 where lower values

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indicate decreased pain, and 2 points is considered clinically significant change. [30] Given our observed

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sample and mean effects between bundle and non-bundle hospitals, we had greater than 80% power to

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detect a MCID in each outcome.

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Eligibility, baseline measures, and operative detail were entered into a web-enabled centralized

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database. [31] The web-application systematically coordinates the multimodal collection of outcomes,

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combining telephone interviews, web-based surveys, and postage-paid reply mail surveys. Surveys were

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collected at one month (37 days postoperative -7/+10), three months (90 days postoperative -10/+14),

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and six months (180 days postoperative -28/+28). We did not include outcomes beyond six months

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because PEPPER is focused on short term safety. Data collection is compliant with the Health Insurance

5

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Portability and Accountability Act, the Code of Federal Regulations Title 21 Part 11, the Federal

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Information Security Modernization Act, and computing principles of minimum necessity, separation of

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duties, and least privilege.

101 102 103

Covariates: We adjusted outcomes for differences in baseline participant characteristics, including age

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(continuous), sex, race (White, Black, other/multiple), ethnicity (Hispanic, not Hispanic), smoking (never,

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current, former), alcohol use (never, monthly or less, two to four times a month, two to three times a

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week, four or more times a week), work status (working, unemployed looking, sick of leave, disabled

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due to hip or knee, disabled for other reasons, student/homemaker/retired), and the number of

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Charlson Comorbidities. [32] Demographics are routinely reported in prediction models for joint

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arthroplasty, [33-41] and comorbidity is associated with poor functional status and adverse outcomes.

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[42-46] Enrolling sites provided height and weight to calculate body mass index (BMI). [47,48] We

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identified facility licensed bed count among PEPPER hospitals from the American Hospital Association’s

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Annual Survey.

113 114 115

Statistical Analysis Methods: Differences in patient characteristics were examined between bundle and non-bundle hospitals

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using χ-square for categorical data and Student’s T-tests for continuous variables. Within each

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procedure cohort (THA/TKA) a linear mixed-effects regression was used to compare differences in

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outcomes through six months based on hospital participation in a bundled payment program, adjusting

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for patient demographics and comorbidity (Appendices 2-3). The model included both patient and

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hospital-level random intercept parameters to adjust standard errors of coefficients for correlated data.

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Variables for age, BMI, number of comorbidities, and PRO’s were included as continuous variables; all 6

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other factors were entered as categorical. Outcomes were adjusted by setting covariates to their mean

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distributions. Inference of the effects of bundled payment was based on the coefficient for an

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interaction between hospital bundled payment status and time (month).

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Data were examined for linearity and influential data points with high leverage. No polynomial

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or interaction terms were required. Participants with missing baseline variables were dropped from the

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regression. Missing responses did not exceed 3.0% (BMI variable missing for 194 participants) for any

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item. Longitudinal regressions estimate summary outcomes for participants with a missing outcome at a

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given follow-up due to survey non-response, individual item missingness, or having not passed through

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the survey window. We additionally examined differences in outcomes after restricting our analysis to

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only those who had completed the study (passed through the six month window) as well as those over

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age 65 only. The findings and conclusions from these sensitivity analyses were consistent with the

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primary results (Appendices 4-7). Because we were uncertain whether the type of bundled payment

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program (BPCI or CJR) would have a heterogeneous effect on our analysis, we also compared outcomes

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between these groups. All analyses were performed using STATA-MP-15 (College Station, TX) with

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hypothesis testing based on an alpha of 0.05. Ethical approval was obtained from the Medical University

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of South Carolina, the central IRB for most sites.

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Results:

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Participant Sites

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Of the 27 PEPPER sites, 25 enrolled patients included in our analysis and 11 of the 25

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participated in Medicare’s BPCI or CJR bundled payment program. Participant sites enrolled 259

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participants on average (range 2-705). PEPPER Hospitals participating in bundled payments had a similar

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volume of beds compared to non-participants (731 vs. 732, p=0.995), and enrolled fewer participants

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into PEPPER on average (198 vs. 299, p=0.211).

145 7

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Participants

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A total of 6,474 patients enrolled in PEPPER were eligible for this analysis, including 1,984

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participants (30.7%) treated by a bundle payment hospital. The median time between completion of the

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baseline survey and undergoing arthroplasty was 8 days. The most common reason for non-participation

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was patient declination. As PEPPER is an ongoing study, not all participants had reached all survey

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windows when data was analyzed. Within the cohort, 5,635 of 6,050 eligible participants (93.1%) had

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completed baseline data collection and at least one postoperative outcome survey. Of eligible

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participants, 82.4%, 79.7%, and 79.3% completed the one, three, and six-month PRO data collections

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respectively (Figure 1).

155 156

Descriptive Data:

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Demographics and comorbidity are provided in Tables 1 and 2, respectively. Compared to non-

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bundle hospitals, participants from bundle hospitals were less likely White (71.4% vs. 82.6%, p<0.001),

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more likely Hispanic (5.2% vs. 1.5%, p<0.001), less likely to be college graduates (38.7% vs. 42.2%,

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p<0.001), less likely to work (37.3% vs 41.4%, p<0.001), and more likely to never drink alcohol (34.5% vs.

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30.4%, p=0.004). Participants in the bundle cohort were more likely to have diabetes (15.9% vs. 13.8%,

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p=0.029), cancer (7.8% vs. 8.5%, p=0.035), kidney disease (3.7% vs. 2.7%, p=0.049), and HIV or AIDS

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(1.6% vs. 0.9%, p=0.010).

164 165

Main Results

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We observed a significant improvement in mean patient-reported function, physical health, and

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pain scores from pre-operative to six months postoperatively for both TKA and THA cohorts, with similar

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improvements found between bundle and non-bundle hospitals (Figures 2-3). To account for baseline

169

differences, estimates were adjusted for age, sex, race, ethnicity, education, work status, alcohol use, 8

170

smoking, and comorbidity. In the TKA cohort, adjusted KOOS Jr. scores increased from 48.4 (95%CI 47.8,

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49.1) at baseline to 75.9 (95%CI 75.1, 76.7) at six months among non-bundle hospitals and from 47.5

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(95%CI 46.5, 48.5) to 73.1 (95%CI 71.9, 74.4) among bundle hospitals, a small but statistically significant

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decrease in improvement of 1.8 points for bundled hospitals (95%CI -3.2, -0.4; p=0.011; Appendix 2). In

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the THA cohort, the adjusted HOOS Jr. scores increased from 49.0 (95%CI 48.1, 49.8) at baseline to 85.2

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(95%CI 84.3, 86.2) at six months among non-bundle hospitals and from 48.7 (95%CI 47.4, 50.1) to 82.7

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(95%CI 81.2, 84.3) among bundle hospitals, a small but statistically significant 2.3 point decrease in

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improvement among bundle hospitals (95%CI -4.0, -0.5; p=0.010; Appendix 3). The PROMIS-PH and

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NPRS scores followed a similar pattern of lower improvement among bundle hospitals with small effect

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sizes (Table 3). No single item within the PRO’s appeared to drive the aggregate score differences.

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The proportions of patients who achieved a MCID in KOOS JR., PROMIS-PH, and NPRS were

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92.6%, 68.1%, and 81.9% respectively following TKA. In the THA cohort, the proportions achieving a

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MCID were 95.6%, 74.9%, and 81.9% for the HOOS JR., PROMIS-PH, and NPRS respectively. There were

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no significant differences in the proportion of participants achieving a MCID in the TKA cohort for any

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measure (Table 4). In the THA cohort, the proportion of participants achieving a MCID was higher in the

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non-bundle cohort for HOOS JR. (96.3% bundle vs. 93.9% non-bundle, p=0.003), but lower in the non-

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bundle cohort for the PROMIS-PH (73.8% bundle vs. 77.3% non-bundle, p=0.045), and NPRS measures

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(81.0% bundle vs. 84.1% non-bundle, p=0.046).

188

Independent of bundled payment status, demographics associated with decreased

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improvements in PROs included female sex, Black race, Hispanic ethnicity, no college education,

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disability, alcohol use, and any smoking history (Appendices 2-3). Having two or more comorbidities was

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associated with poorer PROs for TKA and THA.

192 193

Compared to patients from BPCI participant hospitals, those from CJR hospitals had a lower BMI (31.1 vs. 32.6, p<0.001), were less likely to be female (55.7% vs. 61.7%, p=0.007) or Black (15.6% vs. 9

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31.5%, p<0.001), more likely to be Hispanic (8.8% vs. 1.3%, p<0.001) or have a college degree (42.2%, vs.

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34.9%, p=0.001), and generally had fewer comorbidities. They were similar on age, work status, alcohol,

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and smoking patterns. Regression models (not shown) controlling for age, sex, race, ethnicity, BMI,

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education, work status, alcohol use, smoking status and comorbidity showed no significant differences

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in HOOS JR./KOOS JR., PROMIS-PH, or NPRS between participants enrolled by BPCI or CJR hospitals.

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Discussion:

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Wide variability in hospitals’ episode-of-care costs for joint arthroplasty has led CMMI to pursue

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bundled payment models that incentivize efficiency and care coordination, even with limited

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information on patient impacts. [49,50] Our examination of prospectively collected data from 6,474

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participants undergoing LEJR at 25 hospitals did not reveal major differences in pre-operative to

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postoperative improvements in PROs between bundle and non-bundle payment hospitals. While

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statistically significant differences in PROs improvement were observed favoring hospitals not

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participating in bundle programs, these effect differences were small and the proportion of patients

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who achieved minimum clinically important difference was similar between bundle and non-bundle

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hospitals.

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Our work builds on studies by Doran et al. (2015), [22] who observed no change in PROs after

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adoption of BPCI at a single institution, and Dummit et al. (2016), [14] whose recall survey indicated that

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patients at BPCI and non-BPCI hospitals reported similar functional gains. Our results give reassurance

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that bundled payment hospitals do not provide care leading to meaningfully worse patient-reported

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outcomes, even with concurrent reductions in LEJR costs. [3,4,22,50-53] While small, the differences in

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PROs suggests a need for ongoing monitoring for unintended impacts from bundled payments. Given

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that the largest component of observed cost reduction occurs in post-acute care services, [1,3,4,54]

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patients undergoing more rehabilitation-intensive procedures, such as TKA, might be most impacted by

217

a decrement in services. 10

218

There are several limitations to this study. While PEPPER subjects were randomized to

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anticoagulation prophylaxis, this analysis is nonrandomized, limiting causal inferences. Potential

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differences between participant and non-participant hospitals, including tertiary referral centers,

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public/private hospital, academic status, urban/rural status, or procedure volume were not accounted

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for. Previous studies report that hospitals participating in BPCI had larger procedure volume, greater bed

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counts, and were located in metropolitan centers. [21,55] Accounting for these factors would likely

224

further adjust the observed difference towards the null finding.

225

PEPPER did not recruit patients prior to the start of BPCI, preventing us from comparing pre-to-post

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participation PROs. PEPPER enrolled subjects with a primary indication of osteoarthritis and did not

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ascertain secondary indications, a potential confounder. Although we performed a sensitivity analysis on

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patients over the age of 65 to assess Medicare patients (Appendices 6-7), we cannot determine if care

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pathways were individually modified for these patients. Hospitals considered “non-participatory” may

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have modified care pathways for commercial insurance bundles or in anticipation of starting bundled

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payments, which would bias our findings towards showing no “policy effect”. Despite a 93% response

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rate, the potential impact of participants lost to follow-up is unknown. Due to the ongoing nature of

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PEPPER, we do not include safety and utilization data, such as readmission or ER visits. PROs were

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collected only through six months postoperatively, so differences in longer term outcomes are

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unobserved. Although we had no means to determine if BPCI participation was initiated by surgeons,

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departments, or hospitals at the participant hospitals, we were reassured that there does not appear to

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be heterogeneous outcomes between BPCI and CJR.

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While institutions have adopted various strategies in response to bundled payments, [56] we do not

239

know which (if any) the PEPPER hospitals adopted. One approach is to decrease inpatient length of stay.

240

[52,57] Another is to reduce post-acute care by increasing home discharge or directing patients toward

241

less expensive or shorter post-acute stays. [1,4,17,18,58-61] Other strategies include implant

11

242

standardization [62,63] enhanced care coordination, [51,53] redesigning clinical pathways, [50,52,57]

243

and avoiding or managing high-risk patients. [64] We could not relate specific strategies to PROs. Finally,

244

this study has limited generalizability beyond hip and knee arthroplasty performed at academic medical

245

centers.

246 247

Conclusions:

248

Patients who underwent LEJR at PEPPER hospitals participating in Medicare’s bundled payment

249

programs reported similar short-term improvements in patient-reported global and disease-specific

250

measures of health to those who underwent LEJR at non-bundle hospitals. This finding helps dispel

251

concerns that participation in bundled payment models may lead to poorer outcomes. With the recent

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initiation of the BPCI Advanced, a voluntary bundled payment model for 32 common clinical episodes,

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CMMI is continuing to pursue bundled payment programs. [65] As institutions continue to search for

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new opportunities for cost savings under bundled payments, continued evaluation of PROs can ensure

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cost savings measures do not harm patients.

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References:

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Comprehensive Care for Joint Replacement Payment Model. Final rule; interim final rule with comment period. Fed Regist. 2017;82(230):57066-57104. Navathe AS, Liao JM, Dykstra SE, Wang E, Lyon Z, Shah Y, et al. Association of Hospital Participation in a Medicare Bundled Payment Program With Volume and Case Mix of Lower Extremity Joint Replacement Episodes. JAMA. 2018;320(9):901-910. Joynt Maddox KE, Orav EJ, Zheng J, Epstein AM. Evaluation of Medicare's Bundled Payments Initiative for Medical Conditions. N Engl J Med. 2018;379(3):260-269. Doran JP, Zabinski SJ. Bundled payment initiatives for Medicare and non-Medicare total joint arthroplasty patients at a community hospital: bundles in the real world. J Arthroplasty. 2015;30(3):353-355. Johnson JK, Erickson JA, Miller CJ, Fritz JM, Marcus RL, Pelt CE. Short-term functional recovery after total joint arthroplasty is unaffected by bundled payment participation. Arthroplasty Today. 2019;5(1):119-125. Comparative Effectiveness of Pulmonary Embolism Prevention After Hip and Knee Replacement (PEPPER). https://clinicaltrials.gov/ct2/show/NCT02810704. Accessed November 2nd, 2018. Lyman S, Lee YY, Franklin PD, Li W, Cross MB, Padgett DE. Validation of the KOOS, JR: A Short-form Knee Arthroplasty Outcomes Survey. Clin Orthop Relat Res. 2016;474(6):1461-1471. Lyman S, Lee YY, Franklin PD, Li W, Mayman DJ, Padgett DE. Validation of the HOOS, JR: A Shortform Hip Replacement Survey. Clin Orthop Relat Res. 2016;474(6):1472-1482. Lyman S, Lee YY, McLawhorn AS, Islam W, MacLean CH. What Are the Minimal and Substantial Improvements in the HOOS and KOOS and JR Versions After Total Joint Replacement? Clin Orthop Relat Res. 2018;476(12):2432-2441. Hung M, Bounsanga J, Voss MW, Saltzman CL. Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis outcome score for joint reconstruction in orthopaedics. World J Orthop. 2018;9(3):41. Hung M, Saltzman CL, Greene T, Voss MW, Bounsanga J, Gu Y, et al. Evaluating instrument responsiveness in joint function: The HOOS JR, the KOOS JR, and the PROMIS PF CAT. J Orthop Res. 2018;36(4):1178-1184. Farrar JT, Young Jr JP, LaMoreaux L, Werth JL, Poole RM. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. Pain. 2001;94(2):149-158. www.statix.com. Accessed May 8th, 2019. Charlson M, Szatrowski TP, Peterson J, Gold J. Validation of a combined comorbidity index. J Clin Epidemiol. 1994;47(11):1245-1251. Manning DW, Edelstein AI, Alvi HM. Risk Prediction Tools for Hip and Knee Arthroplasty. J Am Acad Orthop. 2016;24(1):19-27. Sullivan M, Tanzer M, Reardon G, Amirault D, Dunbar M, Stanish W. The role of presurgical expectancies in predicting pain and function one year following total knee arthroplasty. Pain. 2011;152(10):2287-2293. Wuerz TH, Regenbogen SE, Ehrenfeld JM, Malchau H, Rubash HE, Gawande AA, et al. The Surgical Apgar Score in hip and knee arthroplasty. Clin Orthop Relat Res. 2011;469(4):1119-1126. Wuerz TH, Kent DM, Malchau H, Rubash HE. A nomogram to predict major complications after hip and knee arthroplasty. J Arthroplasty. 2014;29(7):1457-1462. Oldmeadow LB, McBurney H, Robertson VJ. Predicting risk of extended inpatient rehabilitation after hip or knee arthroplasty. J Arthroplasty. 2003;18(6):775-779. Mesko NW, Bachmann KR, Kovacevic D, LoGrasso ME, O'Rourke C, Froimson MI. Thirty-day readmission following total hip and knee arthroplasty - a preliminary single institution predictive model. J Arthroplasty. 2014;29(8):1532-1538. 14

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39. Berbari EF, Osmon DR, Lahr B, Eckel-Passow JE, Tsaras G, Hanssen AD, et al. The Mayo prosthetic joint infection risk score: implication for surgical site infection reporting and risk stratification. Infect Control Hosp Epidemiol. 2012;33(8):774-781. 40. Mu Y, Edwards JR, Horan TC, Berrios-Torres SI, Fridkin SK. Improving risk-adjusted measures of surgical site infection for the national healthcare safety network. Infect Control Hosp Epidemiol. 2011;32(10):970-986. 41. Lungu E, Desmeules F, Dionne CE, Belzile EL, Vendittoli PA. Prediction of poor outcomes six months following total knee arthroplasty in patients awaiting surgery. BMC Musculoskelet Disord. 2014;15:299. 42. Belmont PJ, Jr., Goodman GP, Waterman BR, Bader JO, Schoenfeld AJ. Thirty-day postoperative complications and mortality following total knee arthroplasty: incidence and risk factors among a national sample of 15,321 patients. J Bone Joint Surg Am. 2014;96(1):20-26. 43. Edelstein AI, Kwasny MJ, Suleiman LI, Khakhkhar RH, Moore MA, Beal MD, et al. Can the American College of Surgeons Risk Calculator Predict 30-Day Complications After Knee and Hip Arthroplasty? J Arthroplasty. 2015;30(9 Suppl):5-10. 44. Olomu AB, Corser WD, Stommel M, Xie Y, Holmes-Rovner M. Do self-report and medical record comorbidity data predict longitudinal functional capacity and quality of life health outcomes similarly? BMC Health Serv Res. 2012;12:398. 45. Jorgensen CC, Kehlet H. Outcomes in smokers and alcohol users after fast-track hip and knee arthroplasty. Acta Anaesthesiol Scand. 2013;57(5):631-638. 46. Tonnesen H, Kehlet H. Preoperative alcoholism and postoperative morbidity. Br J Surg. 1999;86(7):869-874. 47. Wallace G, Judge A, Prieto-Alhambra D, de Vries F, Arden NK, Cooper C. The effect of body mass index on the risk of post-operative complications during the 6 months following total hip replacement or total knee replacement surgery. Osteoarthritis Cartilage. 2014;22(7):918-927. 48. Foran JR, Mont MA, Etienne G, Jones LC, Hungerford DS. The outcome of total knee arthroplasty in obese patients. J Bone Joint Surg Am. 2004;86-a(8):1609-1615. 49. Miller DC, Gust C, Dimick JB, Birkmeyer N, Skinner J, Birkmeyer JD. Large variations in Medicare payments for surgery highlight savings potential from bundled payment programs. Health Aff (Millwood). 2011;30(11):2107-2115. 50. Froemke CC, Wang L, DeHart ML, Williamson RK, Ko LM, Duwelius PJ. Standardizing Care and Improving Quality under a Bundled Payment Initiative for Total Joint Arthroplasty. J Arthroplasty. 2015;30(10):1676-1682. 51. Althausen PL, Mead L. Bundled Payments for Care Improvement: Lessons Learned in the First Year. J Orthop Trauma. 2016;30 Suppl 5:S50-s53. 52. Iorio R, Clair AJ, Inneh IA, Slover JD, Bosco JA, Zuckerman JD. Early Results of Medicare's Bundled Payment Initiative for a 90-Day Total Joint Arthroplasty Episode of Care. J Arthroplasty. 2016;31(2):343-350. 53. Dundon JM, Bosco J, Slover J, Yu S, Sayeed Y, Iorio R. Improvement in Total Joint Replacement Quality Metrics: Year One Versus Year Three of the Bundled Payments for Care Improvement Initiative. J Bone Joint Surg Am. 2016;98(23):1949-1953. 54. Huckfeldt PJ, Mehrotra A, Hussey PS. The Relative Importance of Post-Acute Care and Readmissions for Post-Discharge Spending. Health Serv Res. 2016;51(5):1919-1938. 55. Navathe AS, Liao JM, Polsky D, Shah Y, Huang Q, Zhu J, et al. Comparison Of Hospitals Participating In Medicare's Voluntary And Mandatory Orthopedic Bundle Programs. Health Aff (Millwood). 2018;37(6):854-863.

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56. Siddiqi A, White PB, Mistry JB, Gwam CU, Nace J, Mont MA, et al. Effect of Bundled Payments and Health Care Reform as Alternative Payment Models in Total Joint Arthroplasty: A Clinical Review. J Arthroplasty. 2017;32(8):2590-2597. 57. Molloy IB, Martin BI, Moschetti WE, Jevsevar DS. Effects of the Length of Stay on the Cost of Total Knee and Total Hip Arthroplasty from 2002 to 2013. J Bone Joint Surg Am. 2017;99(5):402-407. 58. Ryan SP, Goltz DE, Howell CB, Attarian DE, Bolognesi MP, Seyler TM. Skilled Nursing Facilities After Total Knee Arthroplasty: The Time for Selective Partnerships Is Now! J Arthroplasty. 2018;33(12):3612-3616. 59. Zhu JM, Patel V, Shea JA, Neuman MD, Werner RM. Hospitals Using Bundled Payment Report Reducing Skilled Nursing Facility Use And Improving Care Integration. Health Aff (Millwood). 2018;37(8):1282-1289. 60. Luzzi AJ, Fleischman AN, Matthews CN, Crizer MP, Wilsman J, Parvizi J. The "Bundle Busters": Incidence and Costs of Postacute Complications Following Total Joint Arthroplasty. J Arthroplasty. 2018;33(9):2734-2739. 61. Kim K, Iorio R. The 5 Clinical Pillars of Value for Total Joint Arthroplasty in a Bundled Payment Paradigm. J Arthroplasty. 2017;32(6):1712-1716. 62. Lam V, Teutsch S, Fielding J. Hip and knee replacements: A neglected potential savings opportunity. JAMA. 2018;319(10):977-978. 63. Haas DA, Bozic KJ, DiGioia AM, Song Z, Kaplan RS. Drivers of the Variation in Prosthetic Implant Purchase Prices for Total Knee and Total Hip Arthroplasties. J Arthroplasty. 2017;32(2):347350.e343. 64. Karas V, Kildow BJ, Baumgartner BT, Green CL, Attarian DE, Bolognesi MP, et al. Preoperative Patient Profile in Total Hip and Knee Arthroplasty: Predictive of Increased Medicare Payments in a Bundled Payment Model. J Arthroplasty. 2018;33(9):2728-2733.e2723. 65. Centers for Medicare & Medicaid Services. BPCI Advanced. https://innovation.cms.gov/initiatives/bpci-advanced. Accessed September 29th, 2018.

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1 2 3

Acknowledgement: Author Contributions: Mr. Finch had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

4

Study concept and design: Pellegrini, Martin

5

Analysis and interpretation of the data: Finch, Pellegrini, Franklin, Magder, Pelt, Martin

6

Drafting of the manuscript: Finch, Martin

7

Critical revision of the manuscript: Finch, Pellegrini, Franklin, Magder, Pelt, Martin

8

Statistical analysis: Martin, Magder

9

Obtained funding: Pellegrini, Martin, Franklin, Magder

10

Administrative, technical, or material support: Finch, Martin

11

Study Supervision: Pellegrini, Martin

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Collaborators: The PEPPER Trial Investigators: James A. Browne, MD; Charles M. Davis III, MD,

13

PhD; Navin D. Fernando, MD; Kevin B. Fricka, MD; Kevin L. Garvin, MD; Richard Iorio, MD; Michael S.

14

Kain, MD; Stephen L. Kates, MD; Carol A. Lambourne, PhD; Brent A. Lanting, MD, MSc; Carlos J. Lavernia,

15

MD; Brock A. Lindsey, MD; William J. Maloney, MD; Robert M. Molloy, MD; Michael A. Mont, MD;

16

Wayne E. Moschetti, MD, MS; James Nace, DO, MPT; Charles L. Nelson, MD; Kevin I. Perry, MD; James I.

17

Solver, MD; Mark J. Spangehl, MD; Lawrence M. Specht, MD; Scott M. Sporer, MD; Robert M. Sterling,

18

MD; Zeke J. Walton, MD; Lucian C. Warth, MD

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Funding/Support: The research reported in this article was funded through a Patient-Centered Outcomes Research Institute (PCORI) Award (PCS-1402-09328) for the PEPPER trial, and through an

1

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Agency for Healthcare Research and Quality (AHRQ) Award (R01HS024714) for the bundled payment

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analysis.

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Role of the Sponsors: The study sponsors had no role in the design or conduct of the study; the

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collection, management, analysis, and interpretation of the data; or the preparation, review, or approval

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of the manuscript. The statements in this article are solely the responsibility of the authors and do not

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necessarily represent the views of PCORI, AHRQ, or their Board of Governors or Methodology

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Committees.

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Disclaimer: The conclusions and opinions presented herein are those of the authors and not

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necessarily those of PCORI, AHRQ, the University of the Utah School of Medicine, the Medical University

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of South Carolina, the Feinberg School of Medicine, or the University of Maryland School Of Medicine.

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Table 1: Study Cohort Patient Demographics

Non-Bundle (n=4,490)

Bundle (n=1,984)

Alla (n=6,474)

p-valueb

Cohort Knee, n (row %) 2,366 (52.7) 1,115 (56.2) 3,483 (53.8) Hip, n (row %) 2,124 (47.3) 869 (43.8) 2,991 (46.2) Age Age, mean (sd), years 62.8 (10.2) 62.8 (10.6) 62.8 (10.3) 0.923 BMI BMI, mean (sd) 31.7 (6.5) 31.9 (6.6) 31.8 (6.5) 0.376 Sex Male, n (%) 1,913 (42.6) 821 (41.4) 2,732 (42.2) 0.375 Female, n (%) 2,577 (57.4) 1,163 (58.6) 3,742 (57.8) Race White, n (%) 3,709 (82.6) 1,417 (71.4) 5,127 (79.2) Black, n (%) 593 (13.2) 462 (23.3) 1,055 (16.3) <0.001 Other/Multiple, n (%) 189 (4.2) 107 (5.4) 298 (4.6) Ethnicity Not Hispanic, n (%) 4,423 (98.5) 1,881 (94.8) 6,306 (97.4) <0.001 Hispanic or Latino, n (%) 67 (1.5) 103 (5.2) 168 (2.6) Education Less than college, n (%) 2,595 (57.8) 1,216 (61.3) 3,813 (58.9) <0.001 College graduate or higher, n (%) 1,895 (42.2) 768 (38.7) 2,661 (41.1) Work Working, n (%) 1,859 (41.4) 740 (37.3) 2,603 (40.2) Unemployed looking, n (%) 81 (1.8) 40 (2) 123 (1.9) <0.001 Sick of leave, n (%) 741 (16.5) 411 (20.7) 1,152 (17.8) Disabled for other reasons, n (%) 1,800 (40.1) 788 (39.7) 2,590 (40) Alcohol Never, n (%) 1,365 (30.4) 684 (34.5) 2,046 (31.6) Monthly or less, n (%) 1,154 (25.7) 486 (24.5) 1,638 (25.3) Two to four times a month, n (%) 709 (15.8) 290 (14.6) 997 (15.4) 0.004 Two to three times a week, n (%) 674 (15) 252 (12.7) 926 (14.3) Four or more times a week, n (%) 588 (13.1) 272 (13.7) 861 (13.3) Smoke Never, n (%) 2,398 (53.4) 1,109 (55.9) 3,502 (54.1) Current, n (%) 305 (6.8) 117 (5.9) 421 (6.5) 0.117 Former, % 1787 (39.8) 758 (38.2) 2544 (39.3) Table 1 Footnote: Abbreviations: BMI; Body Mass Index. a Due to individual item missingness, not all demographic and comorbidity comparisons sum to complete cohort b Significance testing based on χ-square comparisons for categorical variables, and Student’s T-test for continuous variables.

Table 2: Study Cohort Patient Comorbidity Non-Bundle Bundle Alla p-valueb (n=4,490) (n=1,984) (n=6,474) Comorbidity 211 (4.7) 95 (4.8) 311 (4.8) 0.84 COPD, n (%) 449 (10) 226 (11.4) 673 (10.4) 0.083 Rheumatoid Arthritis, n (%) 620 (13.8) 315 (15.9) 932 (14.4) 0.029 Diabetes, n (%) 382 (8.5) 155 (7.8) 537 (8.3) 0.0354 Cancer, n (%) 90 (2) 36 (1.8) 129 (2) 0.501 Liver disease, n (%) 85 (1.9) 48 (2.4) 129 (2) 0.159 Peripheral Vascular Disease, n (%) 121 (2.7) 73 (3.7) 194 (3) 0.049 Kidney Disease, n (%) 85 (1.9) 46 (2.3) 136 (2.1) 0.311 Ulcer disease, n (%) 40 (0.9) 32 (1.6) 71 (1.1) 0.01 HIV or AIDS, n (%) 31 (0.7) 14 (0.7) 45 (0.7) 0.866 Paralysis, n (%) 184 (4.1) 71 (3.6) 259 (4) 0.333 Heart attack, n (%) 40 (0.9) 28 (1.4) 71 (1.1) 0.101 Carotid artery disease, n (%) 117 (2.6) 56 (2.8) 175 (2.7) 0.57 Stroke, n (%) Table 1 Footnote: Abbreviations: COPD; Chronic Obstructive Pulmonary Disease. HIV; Human Immunodeficiency Virus. AIDS; Acquired Immune Deficiency Syndrome. a Due to individual item missingness, not all demographic and comorbidity comparisons sum to complete cohort b Significance testing based on χ-square comparisons for categorical variables

Table 3: Pre-operative and Post-operative Unadjusted and Adjusted Mean Patient-Reported Outcomes A) NON-BUNDLE BUNDLE TOTAL KNEE ARTHROPLASTY n mean 95%CI n mean Baseline 2,335 48.1 (24.9 - 68.3) 1,083 47.0 1 month 1,743 66.1 (47.5 - 84.6) 758 64.9 Unadjusted 3 month 1,627 73.1 (50.0 - 100) 696 70.9 6 month 1,433 76.3 (52.5 - 100) 606 73.6 KOOS JR Baseline 2,295 48.4 (47.8 - 49.1) 987 47.5 1 month 2,295 65.8 (65.1 - 66.5) 987 64.7 Adjusted 3 month 2,295 72.7 (72.9 - 73.4) 987 70.3 6 month 2,295 75.9 (75.1 - 76.7) 987 73.1 Baseline 2,357 42.3 (32.4 - 54.1) 1,110 41.6 1 month 1,890 46.5 (34.9 - 57.7) 811 46.4 Unadjusted 3 month 1,694 49.9 (37.4 - 61.9) 742 48.6 PROMIS-10 6 month 1,489 50.7 (37.4 - 61.9) 634 49.4 Physical Baseline 2,315 42.6 (42.1 - 43.0) 1,013 41.8 Health 1 month 2,315 46.3 (45.8 - 46.7) 1,013 45.9 Adjusted 3 month 2,315 47.6 (49.1 - 50.0) 1,013 48.1 6 month 2,315 50.4 (49.9 - 50.9) 1,013 48.9 Baseline 2,364 5.4 (1 - 9) 1,115 5.9 1 month 1,905 2.9 (0 - 7) 821 3.1 Unadjusted 3 month 1,710 2.0 (0 - 6) 754 2.5 6 month 1,504 1.8 (0 - 6) 649 2.2 Numeric Pain Rating Baseline 2,322 5.4 (5.2 - 5.5) 1,018 5.8 1 month 2,322 2.9 (2.8 - 3.1) 1,018 3.2 Adjusted 3 month 2,322 2.1 (1.9 - 2.2) 1,018 2.7 6 month 2,322 1.9 (1.7 - 2.0) 1,018 2.4

95%CI (20.9 - 70.7) (42.3 - 84.6) (44.9 - 100) (47.5 - 100) (46.5 - 48.5) (63.6 - 65.9) (69.1 - 71.5) (71.9 - 74.4) (29.6 - 54.1) (34.9 - 57.7) (34.9 - 61.9) (34.9 - 61.9) (41.1 - 42.4) (45.3 - 46.6) (47.4 - 48.7) (48.2 - 49.6) (1 - 10) (0 - 7) (0 - 7) (0 - 7) (5.6 - 6.0) (3.0 - 3.4) (2.5 - 2.9) (2.2 - 2.6)

(Table 3 Cont.) B) NON-BUNDLE BUNDLE n mean 95%CI n mean 95%CI Baseline 2,089 48.4 (20.1 - 73.5) 846 48.5 (15.6 - 76.8) 1 month 1,515 76.5 (53.0 - 100) 611 74.8 (49.9 - 100) Unadjusted 3 month 1,473 82.8 (56.0 - 100) 547 81.2 (53.0 - 100) 6 month 1,328 85.6 (58.9 - 100) 457 83.8 (53.0 - 100) HOOS Jr. Baseline 2,041 49.0 (48.1 - 49.8) 764 48.7 (47.4 - 50.1) 1 month 2,041 76.0 (75.1 - 76.9) 764 73.9 (72.4 - 75.3) Adjusted 3 month 2,041 82.3 (81.3 - 83.2) 764 80.4 (78.8 - 81.9) 6 month 2,041 85.2 (84.3 - 86.2) 764 82.7 (81.2 - 84.3) Baseline 2,118 41.0 (29.6 - 54.1) 863 40.1 (29.6 - 54.1) 1 month 1,660 48.6 (34.9 - 61.9) 656 48.2 (34.9 - 61.9) Unadjusted 3 month 1,534 51.2 (37.4 - 67.7) 557 50.8 (37.4 - 61.9) PROMIS-10 6 month 1,360 52.0 (37.4 - 67.7) 471 51.3 (37.4 - 67.7) Physical Baseline 2,070 41.3 (40.8 - 41.7) 781 41.3 (40.6 - 42.0) Health 1 month 2,070 48.4 (47.9 - 48.9) 781 47.9 (47.1 - 48.6) Adjusted 3 month 2,070 50.9 (50.4 - 51.4) 781 50.3 (49.5 - 51.0) 6 month 2,070 51.6 (51.1 - 52.1) 781 50.8 (50.0 - 51.6) Baseline 2,125 5.8 (1 - 10) 869 6.1 (1 - 10) 1 month 1,686 1.9 (0 - 6) 664 2.0 (0 - 6) Unadjusted 3 month 1,552 1.5 (0 - 6) 569 1.6 (0 - 6) 6 month 1,376 1.4 (0 - 6) 480 1.6 (0 - 6) Numeric Pain Rating Baseline 2,076 5.7 (5.6 - 5.9) 787 6.0 (5.8 - 6.2) 1 month 2,076 1.9 (1.7 - 2.0) 787 2.2 (2.0 - 2.4) Adjusted 3 month 2,076 1.5 (1.4 - 1.7) 787 1.8 (1.6 - 2.1) 6 month 2,076 1.5 (1.3 - 1.7) 787 1.8 (1.5 - 2.0) Table 3 Footnote: Abbreviations: KOOS JR; the brief Knee Osteoarthritis Outcomes Survey. HOOS JR; the brief Hip Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. Adjusted scores included imputed values to account for survey and individual survey item missingness and are adjusted for age, sex, race, ethnicity, education, work status, alcohol use, smoking, and comorbidity. Numeric Pain Rating was assessed using the Numeric Pain Rating Scale (NPRS). TOTAL HIP ARTHROPLASTY

Table 4: Percentage of Patients Achieving a MCID at 6 months PRO Measure Non-Bundle Bundle p-value Total Knee Arthroplasty KOOS JR. 93.2 91.4 0.058 PROMIS 67.4 69.2 0.364 NPRS 76.0 78.1 0.173 Total Hip Arthroplasty HOOS JR. 96.3 93.9 0.003 PROMIS 73.8 77.3 0.045 NPRS 81.0 84.1 0.046 Table 4 Footnote: Abbreviations: PRO; Patient-reported outcome. KOOS JR; the brief Knee Osteoarthritis Outcomes Survey. HOOS JR; the brief Hip Osteoarthritis Outcomes Survey. PROMIS; Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Significance testing based on χ-square comparisons.

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Figures:

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Figure 1: Study Cohort Recruitment and Follow-up

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Figure 1 Legend: *Specific timepoint follow-up rates were calculated using the following formula: # #

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Figure 2: Knee Arthroplasty Adjusted Outcomes

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Figure 2 Legend: Abbreviations: KOOS JR.; the brief Knee Osteoarthritis Outcomes Survey.

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PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health

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Pain Rating is the Numeric Pain Rating Scale (NPRS). Solid lines and circles correspond to non-

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Estimates are adjusted for age, sex, race, ethnicity, education, work status, alcohol use, smoking, and

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comorbidity.

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Figure 3: Hip Arthroplasty Adjusted Outcomes Figure 3 Legend: Abbreviations: HOOS JR.; the brief Hip Osteoarthritis Outcomes Survey.

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PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health

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Summary.

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Pain Rating is the Numeric Pain Rating Scale (NPRS). Solid lines and circles correspond to non-

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bundle participant responses, dashed lines and triangles correspond to bundle participant responses.

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Estimates are adjusted for age, sex, race, ethnicity, education, work status, alcohol use, smoking, and

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comorbidity.

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Appendix 1. PEPPER Enrollment Criteria Inclusion Criteria • • • • • • • •

Age 21 or older Undergoing elective primary, revision or second-stage reimplantation total hip/knee surgery, or unicompartmental knee replacement or hip resurfacing replacement Mental capacity to participate and able to comply with study protocols Able to be randomized to at least two of the three study prophylaxis regimens Negative pregnancy test on day of surgery or other criteria (i.e. sex or reproductive potential) to ensure patient is not pregnant Informed consent Willing to be randomized and to participate in study Surgeon confirmed eligibility for the study

Exclusion Criteria • • • • • • • • • • •

Bilateral hip or knee replacement Previously enrolled in PEPPER trial Pregnant or breastfeeding Chronic (> 6 months) anticoagulation other than with antiplatelet medications Currently enrolled in another active interventional clinical trial testing a drug or intervention know or believed to interact with aspirin, warfarin or rivaroxaban Documented gastrointestinal, cerebral, or other hemorrhage within 3 months of surgery Known history of defective hemostasis and clinical bleeding requiring transfusion and treatment Undergone operative procedure involving eye, ear, or central nervous system within one month of the surgery Severe uncontrolled hypertension with systolic blood pressure greater than 220 mmHg or diastolic blood pressure greater than 120 mmHg Weight less than 41 Kg (90.4 pounds) at pre-operative visit Vulnerable patient population, including prisoners and institutionalized individuals

Appendix 2: Regression Models for Total Knee Arthroplasty KOOS Jr. β (p) 0.0 0.1 0.853 0.0 17.4 0.000*** 24.2 0.000*** 27.5 0.000*** 0.0 −0.2 0.813 −1.5 0.035* −1.8 0.011* 0.2 0.000*** 0.0 −1.4 0.000*** 0.0 0.888 0.0 −3.5 0.000*** 0.5 0.636 0.0 −3.3 0.012* 0.0 1.4 0.001*** 0.0 −2.7 0.061 −4.7 0.000*** −0.5 0.315 0.0 0.2 0.753 0.8 0.204 1.1 0.101 1.7 0.011* 0.0 −2.5 0.005** −1.1 0.006** 0.0 −0.6 0.187 −1.3 0.055 −3.9 0.004** −6.1 0.009** −9.1 0.002** 50.3 0.000***

PROMIS-PH β (p) 0.0 −0.2 0.653 0.0 3.7 0.000*** 7.0 0.000*** 7.8 0.000*** 0.0 0.5 0.104 −0.7 0.023* −0.7 0.032* 0.1 0.000*** 0.0 −1.1 0.000*** −0.1 0.000*** 0.0 −0.7 0.011* −0.1 0.845 0.0 −1.6 0.021* 0.0 1.0 0.000*** 0.0 −2.7 0.000*** −4.5 0.000*** −0.9 0.000*** 0.0 0.0 0.936 1.0 0.001** 1.4 0.000*** 1.9 0.000*** 0.0 −1.7 0.000*** −0.8 0.000*** 0.0 −0.9 0.000*** −2.0 0.000*** −3.9 0.000*** −4.0 0.001** −3.5 0.024* 44.1 0.000***

β 0.0 0.2 0.0 −2.4 −3.3 −3.5 0.0 −0.1 0.2 0.1 −0.0 0.0 0.3 −0.0 0.0 0.8 0.0 0.0 1.1 0.0 −0.3 0.0 0.8 0.9 0.1 0.0 −0.2 −0.4 −0.3 −0.4 0.0 0.7 0.2 0.0 0.1 0.3 0.7 0.4 0.9 5.1

NPRS (p)

Bundle Status (ref = non-bundle) Bundle 0.165 Follow-up (ref = Baseline) 1 month 0.000*** 3 month 0.000*** 6 month 0.000*** Bundle interaction (ref = baseline) 1 month 0.163 3 month 0.034* 6 month 0.374 Age (years) 0.000*** Sex (ref = male) female 0.000*** Body Mass Index 0.289 Race (ref = White) Black 0.000*** Other or Multiple 0.956 Hispanic (ref = No) Yes 0.000*** Education (ref = Less than college degree) College or higher 0.000*** Work status (ref = Working) Unemployed 0.000*** Disabled or on leave 0.000*** Student, homemaker, retired 0.259 Alcohol use (ref = Never) Monthly or less 0.014* Two to four times a month 0.000*** Two to three times a week 0.001*** Four or more times a week 0.000*** Smoking status (ref = Never) Current 0.000*** Former 0.008** Comorbidity count (ref = None) One 0.202 Two 0.002** Three 0.001*** Four 0.255 Five or More 0.035* Constant 0.000*** Variance parameters Center (se) 0.44 (0.39) 0.35 (0.19) 0.04 (0.02) Participant (se) 69.4 (2.9) 23.4 (0.79) 1.46 (0.06) Residual (se) 123.7 (2.1) 23.9 (0.40) 2.99 (0.05) Appendix 2 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: KOOS JR; the brief Knee Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.

Appendix 3: Regression Models for Total Hip Arthroplasty β 0.0 0.2 0.0 27.0 33.3 36.3 0.0 −1.9 −1.7 −2.3 0.1 0.0 −1.6 −0.1 0.0 −3.3 −0.5 0.0 −7.1 0.0 2.2 0.0 −0.9 −6.6 −0.8 0.0 0.5 0.7 1.0 1.7 0.0 −5.7 −2.2 0.0 −1.1 −2.1 −5.7 1.4 −5.9 51.7

KOOS Jr. (p)

PROMIS-PH β (p) 0.0 0.2 0.579 0.0 7.1 0.000*** 9.6 0.000*** 10.4 0.000*** 0.0 −0.6 0.081 −0.7 0.050 −0.9 0.018* 0.0 0.000*** 0.0 −1.5 0.000*** −0.1 0.000*** 0.0 −1.0 0.005** 0.4 0.567 0.0 −2.3 0.007** 0.0 1.1 0.000*** 0.0 −2.4 0.008** −5.4 0.000*** −1.1 0.000*** 0.0 0.6 0.043* 1.1 0.002** 1.7 0.000*** 1.6 0.000*** 0.0 −2.7 0.000*** −1.1 0.000*** 0.0 −1.9 0.000*** −3.2 0.000*** −3.4 0.000*** −2.5 0.105 −5.1 0.000*** 43.6 0.000***

β 0.0 0.2 0.0 −3.9 −4.2 −4.2 0.0 0.0 0.0 0.0 −0.0 0.0 0.2 0.0 0.0 0.7 0.0 0.0 0.8 0.0 −0.4 0.0 0.2 1.1 0.1 0.0 −0.1 −0.1 −0.2 −0.3 0.0 0.6 0.2 0.0 0.1 0.2 0.4 −0.2 0.4 5.5

NPRS (p)

Bundle Status (ref = non-bundle) Bundle 0.758 0.199 Follow-up (ref = Baseline) 1 month 0.000*** 0.000*** 3 month 0.000*** 0.000*** 6 month 0.000*** 0.000*** Bundle interaction (ref = baseline) 1 month 0.018* 0.741 3 month 0.047* 0.976 6 month 0.010* 0.977 Age (years) 0.000*** 0.000*** Sex (ref = male) female 0.000*** 0.000*** Body Mass Index 0.096 0.621 Race (ref = White) Black 0.000*** 0.000*** Other or Multiple 0.682 0.839 Hispanic (ref = No) Yes 0.000*** 0.000*** Education (ref = Less than college degree) College or higher 0.000*** 0.000*** Work status (ref = Working) Unemployed 0.615 0.378 Disabled or on leave 0.000*** 0.000*** Student, homemaker, retired 0.138 0.424 Alcohol use (ref = Never) Monthly or less 0.367 0.074 Two to four times a month 0.329 0.130 Two to three times a week 0.162 0.037* Four or more times a week 0.018* 0.001*** Smoking status (ref = Never) Current 0.000*** 0.000*** Former 0.000*** 0.001** Comorbidity count (ref = None) One 0.038* 0.074 Two 0.013* 0.100 Three 0.001*** 0.092 Four 0.635 0.551 Five or More 0.018* 0.201 Constant 0.000*** 0.000*** Variance parameters Center (se) 1.03 (0.65) 0.35 (0.21) 0.06 (0.03) Participant (se) 75.2 (3.61) 26.48 (0.97) 1.14 (0.06) Residual (se) 147.9 (2.77) 27.43 (0.49) 3.05 (0.06) Appendix 3 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: HOOS JR; the brief Hip Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.

Appendix 4: Regression Models for Total Knee Arthroplasty Completers Only Analysis KOOS Jr. PROMIS-PH NPRS β (p) β (p) β (p) 0.0 0.0 0.0 Bundle Status (ref = non-bundle) Bundle 0.3 0.642 −0.2 0.613 0.1 0.217 Follow-up (ref = Baseline) 0.0 0.0 0.0 1 month 17.6 0.000*** 3.7 0.000*** −2.5 0.000*** 3 month 24.4 0.000*** 7.1 0.000*** −3.3 0.000*** 6 month 27.6 0.000*** 7.9 0.000*** −3.5 0.000*** Bundle interaction (ref = baseline) 0.0 0.0 0.0 1 month −0.6 0.387 0.3 0.271 −0.1 0.549 3 month −2.0 0.008** −0.8 0.008** 0.3 0.007** 6 month −2.1 0.004** −0.7 0.022* 0.1 0.199 Age (years) 0.2 0.000*** 0.1 0.000*** −0.0 0.000*** Sex (ref = male) 0.0 0.0 0.0 female −1.0 0.026* −0.7 0.002** 0.2 0.001** Body Mass Index 0.0 0.862 −0.1 0.000*** −0.0 0.402 Race (ref = White) 0.0 0.0 0.0 Black −3.6 0.000*** −0.7 0.041* 0.8 0.000*** Other or Multiple 1.1 0.339 −0.3 0.630 0.0 0.993 Hispanic (ref = No) 0.0 0.0 0.0 Yes −3.4 0.017* −1.8 0.021* 1.1 0.000*** Education (ref = Less than college degree) 0.0 0.0 0.0 College or higher 1.3 0.006** 1.1 0.000*** −0.3 0.000*** Work status (ref = Working) 0.0 0.0 0.0 Unemployed −2.4 0.125 −2.4 0.003** 0.7 0.001** Disabled or on leave −4.9 0.000*** −4.6 0.000*** 1.0 0.000*** Student, homemaker, retired −0.6 0.264 −0.8 0.003** 0.1 0.105 Alcohol use (ref = Never) 0.0 0.0 0.0 Monthly or less −0.4 0.470 −0.1 0.642 −0.1 0.243 Two to four times a month 0.3 0.634 0.9 0.010* −0.3 0.003** Two to three times a week 1.0 0.164 1.5 0.000*** −0.3 0.006** Four or more times a week 1.5 0.036* 1.8 0.000*** −0.4 0.000*** Smoking status (ref = Never) 0.0 0.0 0.0 Current −2.6 0.009** −1.8 0.001*** 0.7 0.000*** Former −0.9 0.034* −0.7 0.002** 0.1 0.080 Comorbidity count (ref = None) 0.0 0.0 0.0 One −0.7 0.162 −1.0 0.000*** 0.1 0.122 Two −1.6 0.036* −2.2 0.000*** 0.4 0.000*** Three −4.2 0.004** −4.0 0.000*** 0.7 0.001*** Four −6.6 0.014* −4.4 0.002** 0.1 0.707 Five or More −9.4 0.004** −3.2 0.065 1.0 0.033* Constant 50.3 0.000*** 44.0 0.000*** 5.1 0.000*** Appendix 4 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: KOOS JR; the brief Knee Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.

Appendix 5: Regression Models for Total Hip Arthroplasty Completers Only Analysis HOOS Jr. PROMIS-PH NPRS β (p) β (p) β (p) 0.0 0.0 0.0 Bundle Status (ref = non-bundle) Bundle 0.9 0.298 0.5 0.267 0.1 0.489 Follow-up (ref = Baseline) 0.0 0.0 0.0 1 month 26.9 0.000*** 7.1 0.000*** −3.8 0.000*** 3 month 33.2 0.000*** 9.7 0.000*** −4.2 0.000*** 6 month 36.2 0.000*** 10.4 0.000*** −4.3 0.000*** Bundle interaction (ref = baseline) 0.0 0.0 0.0 1 month −2.2 0.014* −0.6 0.099 0.1 0.534 3 month −2.2 0.014* −0.9 0.019* 0.1 0.495 6 month −2.5 0.005** −1.0 0.011* 0.0 0.710 Age (years) 0.1 0.000*** 0.1 0.000*** −0.0 0.000*** Sex (ref = male) 0.0 0.0 0.0 female −1.4 0.003** −1.5 0.000*** 0.2 0.002** Body Mass Index −0.0 0.283 −0.1 0.000*** 0.0 0.983 Race (ref = White) 0.0 0.0 0.0 Black −3.5 0.000*** −1.0 0.009** 0.7 0.000*** Other or Multiple −0.0 0.982 0.5 0.463 0.0 0.778 Hispanic (ref = No) 0.0 0.0 0.0 Yes −7.2 0.000*** −2.2 0.013* 0.8 0.000*** Education (ref = Less than college degree) 0.0 0.0 0.0 College or higher 2.0 0.000*** 1.1 0.000*** −0.3 0.000*** Work status (ref = Working) 0.0 0.0 0.0 Unemployed −0.3 0.855 −2.1 0.029* 0.1 0.536 Disabled or on leave −6.4 0.000*** −5.2 0.000*** 1.1 0.000*** Student, homemaker, retired −0.5 0.401 −1.0 0.002** 0.0 0.647 Alcohol use (ref = Never) 0.0 0.0 0.0 Monthly or less 0.1 0.935 0.9 0.015* −0.2 0.062 Two to four times a month 0.4 0.624 1.4 0.001*** −0.2 0.099 Two to three times a week 0.6 0.412 1.7 0.000*** −0.2 0.108 Four or more times a week 1.2 0.118 1.7 0.000*** −0.3 0.002** Smoking status (ref = Never) 0.0 0.0 0.0 Current −6.0 0.000*** −2.9 0.000*** 0.7 0.000*** Former −2.1 0.000*** −1.1 0.000*** 0.2 0.005** Comorbidity count (ref = None) 0.0 0.0 0.0 One −1.0 0.084 −1.9 0.000*** 0.1 0.261 Two −2.4 0.010** −3.5 0.000*** 0.2 0.072 Three −6.2 0.000*** −4.2 0.000*** 0.4 0.054 Four 0.3 0.932 −3.0 0.068 −0.2 0.615 Five or More −5.5 0.048* −4.9 0.001** 0.5 0.210 Constant 51.9 0.000*** 43.5 0.000*** 5.5 0.000*** Appendix 5 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: HOOS JR; the brief Hip Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.

Appendix 6: Regression Models for Total Knee Arthroplasty Age 65+ Analysis KOOS Jr. PROMIS-PH NPRS β (p) β (p) β (p) 0.0 0.0 0.0 Bundle Status (ref = non-bundle) Bundle −0.7 0.363 −0.5 0.266 0.2 0.069 Follow-up (ref = Baseline) 0.0 0.0 0.0 1 month 16.9 0.000*** 3.5 0.000*** −2.4 0.000*** 3 month 23.9 0.000*** 6.9 0.000*** −3.2 0.000*** 6 month 26.7 0.000*** 7.7 0.000*** −3.4 0.000*** Bundle interaction (ref = baseline) 0.0 0.0 0.0 1 month 0.1 0.937 0.7 0.074 −0.1 0.472 3 month −0.9 0.358 −0.6 0.116 0.2 0.182 6 month −1.1 0.262 −0.7 0.091 0.2 0.203 Age (years) 0.1 0.075 −0.0 0.181 −0.0 0.235 Sex (ref = male) 0.0 0.0 0.0 female −1.6 0.003** −1.1 0.000*** 0.3 0.000*** Body Mass Index 0.0 0.654 −0.1 0.000*** −0.0 0.415 Race (ref = White) 0.0 0.0 0.0 Black −3.0 0.000*** −0.2 0.718 0.6 0.000*** Other or Multiple 0.9 0.517 −0.1 0.859 0.0 0.957 Hispanic (ref = No) 0.0 0.0 0.0 Yes −6.1 0.001*** −2.7 0.004** 1.6 0.000*** Education (ref = Less than college degree) 0.0 0.0 0.0 College or higher 1.7 0.003** 1.4 0.000*** −0.4 0.000*** Work status (ref = Working) 0.0 0.0 0.0 Unemployed −3.6 0.203 −2.3 0.123 0.5 0.185 Disabled or on leave −1.8 0.128 −3.4 0.000*** 0.6 0.001** Student, homemaker, retired −0.1 0.866 −1.1 0.001** 0.1 0.440 Alcohol use (ref = Never) 0.0 0.0 0.0 Monthly or less 0.1 0.914 0.1 0.870 −0.1 0.162 Two to four times a month −0.6 0.480 0.4 0.344 −0.2 0.145 Two to three times a week 1.2 0.190 1.6 0.001*** −0.4 0.003** Four or more times a week 1.7 0.041* 2.0 0.000*** −0.4 0.000*** Smoking status (ref = Never) 0.0 0.0 0.0 Current 2.2 0.185 0.5 0.549 −0.1 0.590 Former −0.6 0.240 −0.4 0.189 0.0 0.741 Comorbidity count (ref = None) 0.0 0.0 0.0 One −0.9 0.149 −1.4 0.000*** 0.1 0.280 Two −2.0 0.024* −2.0 0.000*** 0.4 0.003** Three −4.4 0.008** −4.4 0.000*** 0.8 0.001*** Four −6.6 0.022* −4.7 0.002** 0.3 0.406 Five or More −6.7 0.097 −3.3 0.124 0.5 0.389 Constant 51.2 0.000*** 45.2 0.000*** 5.0 0.000*** Appendix 6 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: KOOS JR; the brief Knee Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.

Appendix 7: Regression Models for Total Hip Arthroplasty Age 65+ Analysis HOOS Jr. PROMIS-PH NPRS β (p) β (p) β (p) 0.0 0.0 0.0 Bundle Status (ref = non-bundle) Bundle −0.8 0.514 −0.3 0.642 0.3 0.108 Follow-up (ref = Baseline) 0.0 0.0 0.0 1 month 26.2 0.000*** 7.1 0.000*** −3.9 0.000*** 3 month 32.1 0.000*** 9.4 0.000*** −4.1 0.000*** 6 month 34.8 0.000*** 10.1 0.000*** −4.1 0.000*** Bundle interaction (ref = baseline) 0.0 0.0 0.0 1 month −1.4 0.258 −0.7 0.161 0.1 0.415 3 month −1.6 0.180 −0.3 0.548 0.0 0.999 6 month −1.2 0.333 0.1 0.834 −0.1 0.441 Age (years) −0.0 0.825 −0.1 0.025* 0.0 0.237 Sex (ref = male) 0.0 0.0 0.0 female −2.1 0.001** −2.0 0.000*** 0.3 0.000*** Body Mass Index −0.1 0.048* −0.2 0.000*** 0.0 0.230 Race (ref = White) 0.0 0.0 0.0 Black −1.5 0.211 −0.1 0.884 0.4 0.010* Other or Multiple 0.7 0.699 0.4 0.710 −0.1 0.800 Hispanic (ref = No) 0.0 0.0 0.0 Yes −2.6 0.371 −0.5 0.735 0.0 0.938 Education (ref = Less than college degree) 0.0 0.0 0.0 College or higher 0.9 0.189 0.7 0.051 −0.3 0.001** Work status (ref = Working) 0.0 0.0 0.0 Unemployed −3.4 0.483 −6.9 0.012* 0.9 0.187 Disabled or on leave −5.0 0.000*** −4.7 0.000*** 1.1 0.000*** Student, homemaker, retired −1.0 0.190 −1.3 0.003** 0.0 0.712 Alcohol use (ref = Never) 0.0 0.0 0.0 Monthly or less 1.2 0.169 1.5 0.002** −0.1 0.311 Two to four times a month 2.0 0.059 1.4 0.014* −0.2 0.092 Two to three times a week 2.6 0.015* 2.3 0.000*** −0.2 0.078 Four or more times a week 2.3 0.020* 1.7 0.002** −0.3 0.044* Smoking status (ref = Never) 0.0 0.0 0.0 Current −4.8 0.006** −2.9 0.002** 0.7 0.004** Former −1.5 0.020* −0.4 0.309 0.1 0.420 Comorbidity count (ref = None) 0.0 0.0 0.0 One −0.8 0.307 −2.0 0.000*** 0.1 0.160 Two −3.1 0.006** −4.1 0.000*** 0.3 0.024* Three −6.3 0.007** −3.7 0.003** 0.5 0.094 Four −2.5 0.482 −5.5 0.005** 0.8 0.087 Five or More −7.0 0.041* −5.4 0.004** 0.1 0.878 Constant 53.8 0.000*** 45.0 0.000*** 5.2 0.000*** Appendix 7 Footnote: * p < 0.05, ** p < 0.01, *** p < 0.001. Abbreviations: HOOS JR; the brief Hip Osteoarthritis Outcomes Survey. PROMIS-PH; the Patient-Reported Outcomes Measurement Information System Physical Health Summary. NPRS; Numeric Pain Rating Scale. Regression model based on multivariable mixed effects regression with robust standard errors clustering for observations within individual patients and patients nested within hospitals.