Variation in Functional Status after Hip Fracture: Facility and Regional Influence on Mobility and Self-Care

Background Recent reports show substantial geographic variation in postacute health care spending. Little is known about variation in functional outcomes after postacute rehabilitation for patients with hip fracture. We examined variation in mobility and self-care after hip fracture rehabilitation across inpatient rehabilitation facilities (IRFs), hospital referral regions (HRRs) and states. Methods Retrospective cohort study using data from the Centers for Medicare and Medicaid Services (CMS) from 2006 to 2009. Study sample included 149,258 records from patients 66 years and older at 1,166 IRFs located within 292 HRRs and across 50 states. Hip fracture cases were defined by CMS impairment group codes (08.11, 08.12). Hierarchical generalized linear models were used to assess discharge mobility and self-care functional status, adjusting for individual patient characteristics and the random effect of IRFs, HRRs, and states. Results Variation in discharge mobility status as assessed by the intraclass correlation percentage (ICC%) was 8.8% across IRFs, 4.0% across HRRs, and 1.8% across states. For self-care, the ICCs were 10.2% across IRFs, 4.8% across HRRs, and 2.4% across states. The range of discharge mobility scores (maximum functional status rating to minimum functional status rating) showed a 9.6-point difference for IRFs, 6.5 for regions, and 2.6 for states. Range of discharge self-care scores were 13.1 for IRFs, 6.8 for HRRs, and 3.4 for states. Conclusion Variation in functional status following postacute hip fracture rehabilitation appears to occur primarily at the level of facilities rather than geographic location.