# Effects of Comprehensive Care for Joint Replacement Model on Racial Disparities in Lower Extremity Joint Replacements

> **NIH NIH R01** · OREGON HEALTH & SCIENCE UNIVERSITY · 2020 · $449,980

## Abstract

Project Summary
Hip and knee replacements improve function and quality of life for people with severe arthritis, yet there have
been long-standing racial disparities in the use and outcomes of these surgeries. Black Americans are about
40-50% less likely to receive hip or knee replacements (also called lower extremity joint replacements, or LEJR)
than whites. Even if they receive LEJR, black patients are more likely to have complications leading to
readmissions or death. Despite national awareness of this issue, this disparity persists.
In April 2016, Medicare implemented the Comprehensive Care for Joint Replacement (CJR) model, a program
that may substantially affect racial disparities in LEJR. The CJR, Medicare's first mandatory bundled payment
program, represents an ambitious attempt to move away from the predominant fee-for-service system with the
potential to serve as a model for future payment systems. Under CJR, hospitals are accountable for the cost of
care for 90 days after patients with LEJR are discharged. An innovative component of CJR is that it is being
implemented in 67 randomly selected metropolitan statistical areas (MSAs). This design provides a unique
opportunity to estimate the causal effect of this payment reform.
The CJR program may have a profound effect on racial disparities. CJR does not adjust for patients'
socioeconomic status when they set target payment rates. This may lead hospitals to avoid admitting LEJR
patients with more complex social service needs during recovery. Since a disproportionately high percentage
of those patients may be black, existing disparities in the receipt of LEJR could be exacerbated. On the other
hand, once the decision is made to provide LEJR, hospitals and post-acute care providers under CJR face new
incentives to work together to improve care coordination for high-needs patients. These changes may reduce
racial disparities in post-acute care following LEJR and patient outcomes of LEJR.
Our proposed research makes use of the unique randomized design of the CJR program to assess its effects
on black-white disparities in LEJR. Our central hypothesis is that CJR increases disparities in the receipt of
LEJR, but reduces disparities in the quality of post-acute care following LEJR and patient outcomes of LEJR.
Specifically, this proposal aims to assess the effect of the CJR program on black-white disparities 1) in the
receipt of LEJR, 2) in post-acute care following LEJR, and 3) in patient outcomes of LEJR.
To assess the effects of the CJR program, we will use Medicare claims to conduct difference-in-difference-in-
differences regressions to examine the effects of CJR on racial disparities at hospitals located in MSAs
affected by CJR relative to hospitals in comparable MSAs elsewhere. Accomplishing these aims will provide
critical knowledge for payment reforms designed to decrease racial disparities not only in LEJR but in health
care more broadly.

## Key facts

- **NIH application ID:** 9850876
- **Project number:** 5R01MD011403-04
- **Recipient organization:** OREGON HEALTH & SCIENCE UNIVERSITY
- **Principal Investigator:** HYUNJEE KIM
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $449,980
- **Award type:** 5
- **Project period:** 2017-05-18 → 2023-01-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9850876

## Citation

> US National Institutes of Health, RePORTER application 9850876, Effects of Comprehensive Care for Joint Replacement Model on Racial Disparities in Lower Extremity Joint Replacements (5R01MD011403-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9850876. Licensed CC0.

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