Association of gynecologic oncology versus medical oncology specialty with survival, utilization, and spending for treatment of gynecologic cancers.

BACKGROUND: We examined the association of gynecologic oncology (GYO) versus medical oncology (MEDONC) based care with survival, health care utilization and spending outcomes in women undergoing chemotherapy for advanced gynecologic cancers. METHODS: Women with newly diagnosed stage III-IV uterine, ovarian, and cervical cancers from 2000 to 2015 were identified in SEER-Medicare. We assessed the association of provider specialty with overall survival, emergency department utilization, admissions, and spending. Outcomes were assessed using unadjusted and Inverse Treatment Probability Weighted propensity-score applied, multi-variable cox modeling, Poisson regression, and generalized models of log-transformed data. RESULTS: We identified 7930 gynecologic cancer patients (4360 ovarian, 2934 uterine, 643 cervix). 37% were treated by GYO and 63% by MEDONC. For ovarian patients, GYO care was associated with improved OS (median OS 3.3 v. 2.9 years; HR 0.85, 95%CI 0.80, 0.91, p < .0001) and similar mean spending per month ($4015 v. $4316, mean ratio 0.97 (95% CI 0.93, 1.02), p = .19), compared to MEDONC in adjusted analyses. For uterine patients, GYO care was associated with similar OS, but decreased spending ($3573 v. $4081, mean ratio 0.87 (95% CI.81, 0.93), p < .0001), and decreased ED utilization (RR 0.76, 95% CI 0.69, 0.85, p < .0001). For cervical patients, GYO care was associated with similar OS, and similar spending. Admissions were more likely in ovarian (RR 1.23, 95%CI 1.11, 1.37, p = .0001) and cervical patients (RR 1.26, 95% CI 1.05, 1.51, p = .015) treated by GYO, in adjusted analyses. CONCLUSIONS: GYO based care was associated with improved OS and equal spending for patients with advanced stage ovarian cancer. Uterine and cervix patients had similar OS, and less or equal spending respectively, when treated by GYO compared to MEDONC.

Prior authorization in gynecologic oncology: An analysis of clinical impact.

BACKGROUND: Prior authorization was designed to minimize unnecessary care and reduce spending but has been associated with delays in necessary care. Our objective was to estimate the occurrence of prior authorization, and impact on cancer care, in gynecologic oncology. METHODS: We performed a retrospective cross-sectional study of patients seen in University of Pennsylvania gynecologic oncology practices (January-March 2021). Using electronic medical records, we measured the incidence of prior authorization during the 3-month period and prior experience of prior authorization for cancer care overall and by type of order (chemotherapy, imaging, surgery, prescription drugs). We assessed the impact of prior authorization occurrence on clinical outcomes (time to service, changes in care). RESULTS: Of the 2112 clinic visits of 1406 unique patients, 5% experienced prior authorization during the 3-month study period. An additional 20% faced prior authorization requests earlier in cancer care. Of the 83 prior authorization requests, imaging accounted for the majority (54%) followed by supportive medications (29%) and chemotherapy (17%). After appeal, 79% of cases were approved. For patients whose prior authorizations were approved, there was a mean of 16 days from order placement to care delivery (95% CI 11-20, range 0-98 days). Of the 17 denials, 3 (18%) led to a substantial change in care (i.e., not receiving planned treatment). CONCLUSION: 25% of gynecologic oncology patients experienced prior authorization during their cancer care. While 80% of claims were ultimately approved, patients experienced over a 2-week delay in care when prior authorization occurred. Reform is needed to reduce the burden of prior authorization in oncology.

Intensity of end-of-life care for gynecologic cancer patients by primary oncologist specialty.

OBJECTIVE: The association of primary oncologist specialty, medical oncology versus gynecologic oncology, on intensity of care at the end of life in elderly patients with gynecologic cancer is unclear. METHODS: This retrospective cohort study used Surveillance, Epidemiology and End Results-Medicare (SEER-M) data. Subjects were fee-for-service Medicare enrollees aged 65 years and older who died of a gynecologic cancer between January 2006 and December 2015. The primary outcome was a composite score for high-intensity care received in the last month of life. Secondary outcomes included invasive procedures and Medicare spending in the last month of life. Simple and multivariable linear and logistic regression analyses evaluated differences in outcomes by primary oncologist specialty. Linear regressions were repeated after creating a more similar control group through nearest-neighbor propensity score matching. RESULTS: Of 12 189 patients, 7705 (63%) had a medical primary oncologist in the last year of life. In adjusted analyses, patients with a gynecologic versus medical primary oncologist received lower rates of high-intensity end-of-life care (53.9% vs 56.6%; p=0.018). Results were similar for the propensity score-matched cohorts. However, having a gynecologic versus medical primary oncologist was associated with higher rates of invasive procedures in the last month of life (43% vs 41%; p=0.014) and higher Medicare spending ($83 859 vs $74 849; p=0.004). CONCLUSIONS: Both specialties engage in overall high levels of intense end-of-life care, with differences by specialty in aspects of aggressive care and spending at the end of life. Physician-level training could be a target for educational or quality improvement initiatives to improve end-of-life cancer care delivery.

An increase in multi-site practices: The shifting paradigm for gynecologic cancer care delivery.

OBJECTIVE: To assess whether the number of practice sites per gynecologic oncologist (GO) and geographic access to GOs has changed over time. METHODS: This is a retrospective repeated cross-sectional study using the 2015-2019 Physician Compare National File. All GOs in the 50 United States and Washington, DC, who had completed at least one year of practice were included in the study. All practice sites with complete addresses were included. Linear regression analyses estimated trends in GOs' number of practice sites and geographic dispersion of practice sites. Secondary analyses assessed temporal trends in the number of geographic areas served by at least one GO. RESULTS: Although there was no significant change in the number of GOs from 2015 to 2019 (n = 1328), there was a significant increase in the number of practice sites (881 to 1416, p = 0.03), zip codes (642 to 984, p = 0.03), HSAs (404 to 536, p = 0.04), and HRRs (218 to 230, p = 0.03) containing a GO practice. The mean number of practice sites (1.64 versus 2.13, p < 0.001) and dispersion of practice sites (0.03 versus 0.43 miles, p = 0.049) per GO increased significantly. CONCLUSIONS: Between 2015 and 2019, an increasing number of GOs have multi-site practices, and more geographic regions contain a GO practice. Improvements in geographic access to GOs may represent improved access to care for many women in the US, but its effect on patients, physicians, and geographic disparities is unknown.

Access to pharmacies and pharmacy services in New York City, Los Angeles, Chicago, and Houston, 2015-2020.

BACKGROUND: Despite the importance of pharmacies in ensuring medications and health care needs are met, there is limited up-to-date information regarding access to pharmacies or their services in the United States. OBJECTIVES: To evaluate trends and disparities in access to pharmacies in 4 largest cities in the United States, New York City, Los Angeles, Houston, and Chicago, by neighborhood racial and ethnic composition from 2015 to 2020. METHODS: Data from the National Council for Prescription Drug Programs (2015-2020) and the American Community Survey (2015-2019) were used. We examined neighborhoods (i.e., census tracts) and evaluated disparities in "pharmacy deserts" (low-income neighborhoods (1) whose average distance to the nearest pharmacy was at least 1 mile or (2) whose average distance to the nearest pharmacy was at least 0.5 mile and at least 100 households had no vehicle access). We also evaluated the differences in pharmacy closures and the availability of pharmacy services. RESULTS: From 2015 to 2020, the percent of neighborhoods with pharmacy deserts declined in New York City (from 1.6% to 0.9% of neighborhoods, P < 0.01), remained stable in Los Angeles (13.7% to 13.4%, P = 0.58) and Houston (27.0% to 28.5%, P = 0.18), and increased in Chicago (15.0% to 19.9%, P < 0.01). Pharmacy deserts were persistently more common in Black and Latino neighborhoods in all 4 cities. As of 2020, pharmacies in Black and Latino neighborhoods were also more likely to close and less likely to offer immunization, 24-hour, and drive-through services than pharmacies in other neighborhoods. CONCLUSION: To reduce disparities in access to medications and health care services, including those in response to the coronavirus disease 2019 pandemic (e.g., testing and vaccinations), policies that improve pharmacy access and expand the provision of pharmacy services in minority neighborhoods are critical.

The Effects of Market Competition on Cardiologists' Adoption of Transcatheter Aortic Valve Replacement.

BACKGROUND: For decades, the prevailing assumption regarding the diffusion of high-cost medical technologies has been that competitive markets favor more aggressive adoption of new treatments by health care providers (ie, the "Medical Arms Race"). However, novel regulations governing the adoption of transcatheter aortic valve replacement (TAVR) may have disrupted this paradigm when TAVR was introduced. OBJECTIVE: The objective of this study was to assess the relationship between the market concentration of physician group practices and the adoption of TAVR in its first years of use. RESEARCH DESIGN: This was a retrospective cohort study. SUBJECTS: Physician group practices (n=5116) providing interventional cardiology services in the United States from May 1, 2012, to December 31, 2014. MEASURES: The first use of TAVR as indicated by a fee-for-service Medicare claim. Covariates including characteristics of the physician groups (ie, case volume, hospital affiliation, mean patient risk) as well as county-level and market-level characteristics. RESULTS: By the close of 2014, 9.3% of practices had adopted TAVR. Cox proportional hazards models revealed a hazard ratio of 1.26 (95% confidence interval: 1.16-1.37, P<0.001) per 1000 point increase in the physician group practice Herfindahl-Hirschman Index, indicating each 1000 point increase in group practice Herfindahl-Hirschman Index was associated with a 26% relative increase in the rate of TAVR adoption. CONCLUSIONS: Adoption of TAVR by physician groups in concentrated markets was potentially a consequence of the unique regulations governing TAVR reimbursement, which favored the adoption of TAVR by physician groups with greater market power. These findings have important implications for how future regulations may shape patterns of technology adoption.

Neighborhood price of healthier food relative to unhealthy food and its association with type 2 diabetes and insulin resistance: The multi-ethnic study of atherosclerosis.

This study examined the association between the price of healthier food relative to unhealthy food and type 2 diabetes prevalence, incidence and insulin resistance (IR). Data came from the Multi-Ethnic Study of Atherosclerosis exam 5 administered 2010-2012 (exam 4, five years prior, was used only for diabetes incidence) and supermarket food/beverage prices derived from Information Resources Inc. For each individual, average price of a selection of healthier foods, unhealthy foods and their ratio was computed for supermarkets within 3miles of the person's residential address. Diabetes status was confirmed at each exam and IR was assessed via the homeostasis model assessment index. Multivariable-adjusted logistic, modified Poisson and linear regression models were used to model diabetes prevalence, incidence and IR, respectively as a function of price and covariates; 2353 to 3408 participants were included in analyses (depending on the outcome). A higher ratio of healthy-to-unhealthy neighborhood food price was associated with greater IR (4.8% higher HOMA-IR score for each standard deviation higher price ratio [95% CI -0.2% to 10.1%]) after adjusting for region, age, gender, race/ethnicity, family history of diabetes, income/wealth index, education, smoking status, physical activity, and neighborhood socioeconomic status. No association with diabetes incidence (relative risk=1.11, 95% CI 0.85 to 1.44) or prevalence (odds ratio=0.95, 95% CI 0.81 to 1.11) was observed. Higher neighborhood prices of healthier food relative to unhealthy food were positively associated with IR, but not with either diabetes outcome. This study provides new insight into the relationship between food prices with IR and diabetes.

Health Care Privacy Risks of AI Chatbots.

This Viewpoint notes that as clinicians incorporate new AI tools (such as chatbots) into their practice, they must also remain vigilant of the risks these tools pose to other aspects of patient care such as privacy.

Public Awareness of and Contact With Physicians Who Receive Industry Payments: A National Survey.

BACKGROUND: The Physician Payments Sunshine Act, part of the Affordable Care Act, requires pharmaceutical and medical device firms to report payments they make to physicians and, through its Open Payments program, makes this information publicly available. OBJECTIVE: To establish estimates of the exposure of the American patient population to physicians who accept industry payments, to compare these population-based estimates to physician-based estimates of industry contact, and to investigate Americans' awareness of industry payments. DESIGN: Cross-sectional survey conducted in late September and early October 2014, with data linkage of respondents' physicians to Open Payments data. PARTICIPANTS: A total of 3542 adults drawn from a large, nationally representative household panel. MAIN MEASURES: Respondents' contact with physicians reported in Open Payments to have received industry payments; respondents' awareness that physicians receive payments from industry and that payment information is publicly available; respondents' knowledge of whether their own physician received industry payments. KEY RESULTS: Among the 1987 respondents who could be matched to a specific physician, 65% saw a physician who had received an industry payment during the previous 12 months. This population-based estimate of exposure to industry contact is much higher than physician-based estimates from the same period, which indicate that 41% of physicians received an industry payment. Across the six most frequently visited specialties, patient contact with physicians who had received an industry payment ranged from 60 to 85%; the percentage of physicians with industry contact in these specialties was much lower (35-56%). Only 12% of survey respondents knew that payment information was publicly available, and only 5% knew whether their own doctor had received payments. CONCLUSIONS: Patients' contact with physicians who receive industry payments is more prevalent than physician-based measures of industry contact would suggest. Very few Americans know whether their own doctor has received industry payments or are aware that payment information is publicly available.

Healthy and Unhealthy Food Prices across Neighborhoods and Their Association with Neighborhood Socioeconomic Status and Proportion Black/Hispanic.

This paper evaluates variation in food prices within and between neighborhoods to improve our understanding of access to healthy foods in urbanized areas and potential economic incentives and barriers to consuming a higher-quality diet. Prices of a selection of healthier foods (dairy, fruit juice, and frozen vegetables) and unhealthy foods (soda, sweets, and salty snacks) were obtained from 1953 supermarkets across the USA during 2009-2012 and were linked to census block group socio-demographics. Analyses evaluated associations between neighborhood SES and proportion Black/Hispanic and the prices of healthier and unhealthy foods, and the relative price of healthier foods compared with unhealthy foods (healthy-to-unhealthy price ratio). Linear hierarchical regression models were used to explore geospatial variation and adjust for confounders. Overall, the price of healthier foods was nearly twice as high as the price of unhealthy foods ($0.590 vs $0.298 per serving; healthy-to-unhealthy price ratio of 1.99). This trend was consistent across all neighborhood characteristics. After adjusting for covariates, no association was found between food prices (healthy, unhealthy, or the healthy-to-unhealthy ratio) and neighborhood SES. Similarly, there was no association between the proportion Black/Hispanic and healthier food price, a very small positive association with unhealthy price, and a modest negative association with the healthy-to-unhealthy ratio. No major differences were seen in food prices across levels of neighborhood SES and proportion Black/Hispanic; however, the price of healthier food was twice as expensive as unhealthy food per serving on average.

Attitudes, practices, and preparedness to care for patients with substance use disorder: Results from a survey of general internists.

BACKGROUND: Previous research demonstrates that most primary care physicians feel unprepared to diagnose and treat substance use disorder (SUD). Confidence in SUD management has been associated with improved clinical practices. METHODS: A cross-sectional survey of 290 inpatient and outpatient general internists in an academic medical center evaluating attitudes, preparedness, and clinical practice related to SUD. RESULTS: 149 general internists responded, a response rate of 51%. Forty-six percent frequently cared for patients with SUD. Sixteen percent frequently referred patients to treatment and 6% frequently prescribed a medication to treat SUD. Twenty percent felt very prepared to screen for SUD, 9% to provide a brief intervention, 7% to discuss behavioral treatments, and 9% to discuss medication treatments. Thirty-one percent felt that SUD is different from other chronic diseases because they believe using substances is a choice. Fourteen percent felt treatment with opioid agonists was replacing one addiction with another. Twelve percent of hospitalists and 6% of PCPs believe that someone who uses drugs is committing a crime and deserves punishment. Preparedness was significantly associated with evidence-based clinical practice and favorable attitudes. Frequently caring for patients with SUD was significantly associated with preparedness, clinical practice, and favorable attitudes. CONCLUSIONS: SUD is a treatable and prevalent disease, yet a majority of general internists do not feel very prepared to screen, diagnose, provide a brief intervention, refer to treatment, or discuss treatment options with patients. Very few frequently prescribe medications to treat SUD. Some physicians view substance use as a crime and a choice. Physician preparedness and exposure to SUD is associated with improved clinical practice and favorable attitudes towards SUD. Physicians need education and support to provide better care for patients with SUD.

Medicine Resident Preparedness to Diagnose and Treat Substance Use Disorders: Impact of an Enhanced Curriculum.

BACKGROUND: The authors' previous study found that despite caring for many patients with addiction, most Massachusetts General Hospital (MGH) internal medicine residents feel unprepared to treat substance use disorders (SUDs) and rate SUD instruction during training as fair or poor. This follow-up study evaluates the impact of an enhanced curriculum on resident perceptions of the quality of instruction, knowledge base, and self-perceived preparedness to diagnose and treat SUDs. METHODS: Based on the findings of the earlier study, an enhanced SUD curriculum was designed and delivered to MGH medicine residents. Impact of the curriculum was evaluated using the same Web-based survey that was administered in the earlier study to compare pre- and posttest results. RESULTS: The authors' earlier study found that 75% of residents felt prepared to diagnose and 37% to treat SUDs and 45% of residents rated the overall quality of SUD instruction as good or excellent. Following the curriculum intervention, 87% of residents reported feeling prepared to diagnose (P=.028) and 60% to treat (P=.002) SUDs. Three quarters of residents rated the overall quality of instruction as good or excellent (P<.001), and 98% reported residency curriculum had a positive impact on their preparedness to care for patients with a SUDs. Residents who reported receiving an adequate amount of SUD instruction were more likely to feel prepared to diagnose and treat addiction (P<.001). Thirty-one percent of residents still rated the overall amount of SUD instruction as too little. The intervention did not significantly improve answers to knowledge questions. CONCLUSIONS: An enhanced SUDs curriculum for medicine residents increased self-perceived preparedness to diagnose and treat SUDs and educational quality ratings. However, there was no significant change in knowledge. Implementation of a more comprehensive curriculum and evaluation at other sites are necessary to determine the ideal SUD training model.

Act II of the Sunshine Act.

To coincide with the introduction in the United States of the Sunshine Act, Genevieve Pham-Kanter discusses what we need to look for to fight hidden bias and deliberate or unconscious corruption. Please see later in the article for the Editors' Summary.

Revisiting financial conflicts of interest in FDA advisory committees.

CONTEXT: The Food and Drug Administration (FDA) Safety and Innovation Act has recently relaxed conflict-of-interest rules for FDA advisory committee members, but concerns remain about the influence of members' financial relationships on the FDA's drug approval process. Using a large newly available data set, this study carefully examined the relationship between the financial interests of FDA Center for Drug Evaluation and Research (CDER) advisory committee members and whether members voted in a way favorable to these interests. METHODS: The study used a data set of voting behavior and reported financial interests of 1,379 FDA advisory committee members who voted in CDER committee meetings that were convened during the 15-year period of 1997-2011. Data on 1,168 questions and 15,739 question-votes from 379 meetings were used in the analyses. Multivariable logit models were used to estimate the relationship between committee members' financial interests and their voting behavior. FINDINGS: Individuals with financial interests solely in the sponsoring firm were more likely to vote in favor of the sponsor than members with no financial ties (OR = 1.49, p = 0.03). Members with interests in both the sponsoring firm and its competitors were no more likely to vote in favor of the sponsor than those with no financial ties to any potentially affected firm (OR = 1.16, p = 0.48). Members who served on advisory boards solely for the sponsor were significantly more likely to vote in favor of the sponsor (OR = 4.97, p = 0.005). CONCLUSIONS: There appears to be a pro-sponsor voting bias among advisory committee members who have exclusive financial relationships with the sponsoring firm but not among members who have nonexclusive financial relationships (ie, those with ties to both the sponsor and its competitors). These findings point to important heterogeneities in financial ties and suggest that policymakers will need to be nuanced in their management of financial relationships of FDA advisory committee members.

Association between oral targeted cancer drug net health benefit, uptake, and spending.

BACKGROUND: Targeted cancer drugs (TCDs) have revolutionized oncology but vary in clinical benefit and patient out-out-pocket (OOP) costs. The ASCO Value Framework uses survival, toxicity, and symptom palliation data to quantify the net health benefit (NHB) of cancer drugs. We evaluated associations between NHB, uptake, and spending on oral TCDs. METHODS: We conducted a retrospective cohort study of patients aged 18-64 years with an incident oral TCD pharmacy claim in 2012-2020 in a nationwide de-identified commercial claims dataset. TCDs were categorized as having high (>60), medium (40-60), and low (<40) NHB scores. We plotted the uptake of TCDs by NHB category and used standard descriptive statistics to evaluate patient OOP and total spending. Generalized linear models evaluated the relationship between spending and TCD NHB, adjusted for cancer indication. RESULTS: We included 8,524 patients with incident claims for eight oral TCDs with nine first-line indications in advanced melanoma, breast, lung, and pancreatic cancer. Medium- and high-NHB TCDs accounted for most TCD prescriptions. Median OOP spending was $18.78 for the first 28-day TCD supply (IQR $0.00-$87.57); 45% of patients paid $0 OOP. Median total spending was $10,118.79 (IQR $6,365.95-$10,600.37) for an incident 28-day TCD supply. Total spending increased $1,083.56 for each 10-point increase in NHB score (95% CI $1,050.27-$1,116.84, p < .01 for H0=$0). CONCLUSION: Low-NHB TCDs were prescribed less frequently than medium- and high-NHB TCDs. Total spending on oral TCDs was high and positively associated with NHB. Commercially insured patients were largely shielded from high OOP spending on oral TCDs.

Cancer Treatment Before and After Physician-Pharmacy Integration.

Importance: Integration of pharmacies with physician practices, also known as medically integrated dispensing, is increasing in oncology. However, little is known about how this integration affects drug use, expenditures, medication adherence, or time to treatment initiation. Objective: To examine the association of physician-pharmacy integration with oral oncology drug expenditures, use, and patient-centered measures. Design, Setting, and Participants: This cohort study used claims data from a large commercial insurer in the US to analyze changes in outcome measures among patients treated by pharmacy-integrating vs nonintegrating community oncologists in 14 states between January 1, 2011, and December 31, 2019. Commercially insured patients were aged 18 to 64 years with 1 of the following advanced-stage diagnoses: breast cancer, colorectal cancer, kidney cancer, lung cancer, melanoma, or prostate cancer. Data analysis was conducted from May 2023 to March 2024. Exposure: Treatment by a pharmacy-integrating oncologist, ascertained by the presence of an on-site pharmacy or nonpharmacy dispensing site. Main Outcomes and Measures: Oral, intravenous (IV), total, and out-of-pocket drug expenditures for a 6-month episode of care; share of patients prescribed oral drugs; days' supply of oral drugs; medication adherence measured by proportion of days covered; and time to treatment initiation. The association between an oncologist's pharmacy integration and each outcome of interest was estimated using the difference-in-differences estimator. Results: Between 2012 and 2019, 3159 oncologists (745 females [27.1%], 2002 males [72.9%]) treated 23 968 patients (66.4% female; 53.4% aged 55-64 years). Of the 3159 oncologists, 578 (18.3%) worked in practices that integrated with pharmacies (with a low rate in 2011 of 0% and a high rate in 2019 of 31.5%). In the full sample (including all cancer sites), after physician-pharmacy integration, no significant changes were found in oral drug expenditures, IV drug expenditures, or total drug expenditures. There was, however, an increase in days' supply of oral drugs (5.96 days; 95% CI, 0.64-11.28 days; P = .001). There were no significant changes in out-of-pocket expenditures, medication adherence, or time to treatment initiation of oral drugs. In the breast cancer sample, there was an increase in oral drug expenditures ($244; 95% CI, $41-$446; P = .02) and a decrease in IV drug expenditures (-$4187; 95% CI, -$8293 to -$80; P = .05). Conclusions and Relevance: Results of this cohort study indicated that the integration of oncology practices with pharmacies was not associated with significant changes in expenditures or clear patient-centered benefits.

Association between mandatory bundled payments and changes in socioeconomic disparities for joint replacement outcomes.

OBJECTIVE: To determine whether mandatory participation by hospitals in bundled payments for lower extremity joint replacement (LEJR) was associated with changes in outcome disparities for patients dually eligible for Medicare and Medicaid. DATA SOURCES AND STUDY SETTING: We used Medicare claims data for beneficiaries undergoing LEJR in the United States between 2011 and 2017. STUDY DESIGN: We conducted a retrospective observational study using a differences-in-differences method to compare changes in outcome disparities between dual-eligible and non-dual eligible beneficiaries after hospital participation in the Comprehensive Care for Joint Replacement (CJR) program. The primary outcome was LEJR complications. Secondary outcomes included 90-day readmissions and mortality. DATA EXTRACTION METHODS: We identified hospitals in the US market areas eligible for CJR. We included beneficiaries in the intervention group who received joint replacement at hospitals in markets randomized to participate in CJR. The comparison group included patients who received joint replacement at hospitals in markets who were eligible for CJR but randomized to control. PRINCIPAL FINDINGS: The study included 1,603,555 Medicare beneficiaries (mean age, 74.6 years, 64.3% women, 11.0% dual-eligible). Among participant hospitals, complications decreased between baseline and intervention periods from 11.0% to 10.1% for dual-eligible and 7.0% to 6.4% for non-dual-eligible beneficiaries. Among nonparticipant hospitals, complications decreased from 10.3% to 9.8% for dual-eligible and 6.7% to 6.0% for non-dual-eligible beneficiaries. In adjusted analysis, CJR participation was associated with a reduced difference in complications between dual-eligible and non-dual-eligible beneficiaries (-0.9 percentage points, 95% CI -1.6 to -0.1). The reduction in disparities was observed among hospitals without prior experience in a voluntary LEJR bundled payment model. There were no differential changes in 90-day readmissions or mortality. CONCLUSIONS: Mandatory participation in a bundled payment program was associated with reduced disparities in joint replacement complications for Medicare beneficiaries with low income. To our knowledge, this is the first evidence of reduced socioeconomic disparities in outcomes under value-based payments.