Reliability and Validity of the Inpatient Rehabilitation Facility Discharge Mobility and Self-Care Quality Measures

Abstract

Objective: To describe the reliability and validity of the publicly reported facility-level quality measures Inpatient Rehabilitation Facility (IRF) Discharge Mobility Score for Medical Rehabilitation Patients ("Discharge mobility score") and IRF Discharge Self-Care Score for Medical Rehabilitation Patients ("Discharge self-care score").

Design: Observational study using standardized patient assessment data to examine facility-level split-half reliability and construct validity of quality measure scores.

Setting and participants: All IRFs (n = 1117) in the United States with at least 20 Medicare stays. Facility-level quality measure scores were calculated from 2017 data on 428,192 Medicare (fee-for-service and Medicare Advantage) IRF patient stays.

Methods: Using clinician-reported assessment data, we calculated facility-level mobility and self-care quality measure scores and examined reliability of these scores using split-half analysis and Pearson product-moment correlations, Spearman rank correlations, and intraclass correlation coefficients (ICC_2,1). We examined construct validity of these scores by comparing facility-level quality measure scores by facility stroke disease-specific certification status.

Results: Reported as percentages meeting or exceeding expectations, IRF quality measure scores ranged from 8.3% to 90.1% for mobility and 9.0% to 90.3% for self-care. IRF scores, when split in half to examine reliability, showed strong, positive correlations for the mobility (Pearson = 0.898, Spearman = 0.898, ICC = 0.898) and self-care (Pearson = 0.886, Spearman = 0.874, ICC = 0.886) scores. When stratified by provider volume, ICCs remained strong. Construct validity analyses showed IRFs with stroke disease-specific certification had higher mean and median scores than IRFs without certification, and a greater proportion of IRFs that were certified had higher scores.

Conclusion and implications: Our results support the reliability and construct validity of the IRF quality measures Discharge mobility and Discharge self-care scores. Reported as percentages meeting or exceeding expectations, these quality measures are designed to be more consumer-friendly compared to change scores.

Keywords: Functional status; public reporting of health care data; quality measure; rehabilitation; risk adjustment; treatment outcome.