A1067
Title: Regional variation of length of stay in inpatient rehabilitation facilities and the market-level influencing factors
Authors: Jessica Cao - University of Wisconsin-Madison (United States) [presenting]
Abstract: The aim is to 1) measure the regional variation of length of stay (LOS) for post-acute care delivered in inpatient rehabilitation facilities (IRF); and 2) identify market-level factors and quantify their effects on regional variation. A multi-year cross-sectional design is adopted, and data from the Uniform Data System for Medical Rehabilitation (UDSMR) are used. The sample included IRF admissions for US Medicare beneficiaries 65 years or older with stroke as a primary diagnosis from January 2019 to December 2020. The primary outcomes are regional variations by Medicare coverage type (TM vs MA) and pandemic timing (before vs during). Cross-region variation is calculated as the variance of average risk-adjusted LOS for 10 CMS regions. Within-region variation is calculated as the variance of risk-adjusted LOS for all admissions within a region. The main explanatory variables included regional-level Medicare Advantage penetration and IRF market consolidation measured by Herfindahl Index (HHI). Risk adjustment included sociodemographic variables, clinical conditions, and facility characteristics. Results suggested that administrative variations in MA plans contribute to regional variation in LOS for MA-covered admissions, especially in regions with high MA penetration or low IRF market consolidation. Uniform administration and market consolidation can help reduce regional variation.