Geographic Variation in Inpatient Rehabilitation Outcomes After Traumatic Brain Injury.

Objective: To determine whether regional variations exist in functional outcomes of patients with traumatic brain injury (TBI) admitted to inpatient rehabilitation facilities (IRFs) across the United States, while controlling for demographic and clinical variables.

Setting: Inpatient rehabilitation facilities (IRFs) across 4 U.S. regions: West, Midwest, South, and East.

Participants: Adult patients with open or closed TBI (Rehabilitation Impairment Codes 2.21 or 2.22) discharged from an IRF between 2016 and 2019.

Design: This is a retrospective analysis de-identified data from the Uniform Data System for Medical Rehabilitation. The study compared total functional independence measure (FIM) scores and discharge dispositions across the 4 regions.

Main measures: Primary outcomes were FIM scores at discharge, changes in FIM scores between admission and discharge, and community discharge rates, adjusted for demographic and clinical factors. Cohen's d effect sizes were calculated to assess the clinical significance of regional differences on FIM scores. Prevalence ratios were used for discharge disposition outcomes.

Results: Regional differences were identified in functional outcomes for patients with TBI. The West had the highest community discharge rate (80.9%) compared to the East (70.5%). Discharge FIM scores were significantly lower in the Midwest and East compared to the South (-1.98 and - 2.31, respectively, P < .01), while the West showed no significant difference from the South (-0.78, P = .11). Effect sizes for FIM total scores were small across regions, with Cohen's d for West versus South at 0.017, Midwest versus South at 0.047, and East versus South at 0.047. Prevalence ratios for community discharge showed minor differences: West versus South at 1.010, Midwest versus South at 0.937, and East versus South at 0.918; all without statistical significance.

Conclusions: Regional disparities in functional outcomes following inpatient rehabilitation for TBI were observed, particularly in community discharge rates and total FIM scores. However, based on the effect sizes and prevalence ratios, these differences may not be clinically meaningful and could not be fully explained by demographic and clinical factors. Further studies are needed to explore region-specific factors influencing rehabilitation efficacy to improve outcomes for patients with TBI nationwide.