Abstract
BACKGROUND: The Comprehensive Care for Joint Replacement (CJR) model is an alternative Medicare payment model for joint replacement that mandated participation by hospitals in randomly selected Metropolitan Statistical Areas (MSAs). On average, the program decreased inpatient length of stay and increased home discharge rates. It is unclear if these effects differed based on hospital ownership type, even though ownership may impact care redesign opportunities. METHODS: We used the 2014-2017 California Patient Discharge Datasets. The study included 113,590 hospitalizations for hip and knee joint replacement from 287 hospitals in the treated and control MSAs in California. The primary outcomes were inpatient length of stay and home discharge rates. Home discharge status included self-care, the use of home health, and hospice care at home. To determine whether the impact of the CJR model differed by hospital ownership type, we used event study, difference-in-differences (DID), and triple differences (DDD) models to estimate changes in health care services utilization in treated relative to control areas before versus after CJR implementation (April 2016) by hospital ownership type. RESULTS: Of the 113,590 hospitalizations, 51,708 (45.52%) were in treated MSAs and 61,882 (54.48%) were in control MSAs; 81,649 (71.88%) were from nonprofit hospitals, 20,247 (17.82%) were from for-profit hospitals, and 11,694 (10.29%) were from government-owned hospitals. DID analyses showed that after policy implementation, nonprofit and for-profit hospitals experienced a decrease in inpatient length of stay of 0.02 days (95% CI, -0.04 to -0.01) and 0.04 days (95% CI, -0.06 to -0.01), respectively, while government-owned hospitals experienced an increase by 0.11 days (95% CI, 0.04 to 0.18). For home discharge rates, nonprofit hospitals experienced an increase of 0.02 (95% CI, 0.01 to 0.03), while other hospitals did not show statistically significant changes. DDD analyses confirmed that inpatient length of stay increased in public compared to nonprofit hospitals in treated relative to control MSAs after policy implementation. CONCLUSIONS: The impacts of the CJR program differed by hospital ownership type. Government-owned hospitals, with their unique financial circumstances, may have faced challenges that hindered the reductions in inpatient length of stay observed in other types of hospitals under the CJR Model.