Comparison of the VA and NIDILRR TBI model system cohorts

Objective: Within the same time frame, compare the National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) and VA Traumatic Brain Injury Model System (TBIMS) data sets to inform future research and generalizability of findings across cohorts. Setting: Inpatient comprehensive interdisciplinary rehabilitation facilities. Participants: Civilians, Veterans, and active duty service members in the VA (n = 550) and NIDILRR civilian settings (n = 5270) who were enrolled in TBIMS between August 2009 and July 2015. Design: Prospective, longitudinal, multisite study. Main Measures: Demographics, Injury Characteristics, Functional Independence Measures, Disability Rating Scale. Results: VA and NIDILRR TBIMS participants differed on 76% of comparisons (18 Important, 8 Minor), with unique differences shown across traumatic brain injury etiology subgroups. The VA cohort was more educated, more likely to be employed at the time of injury, utilized mental health services premorbidly, and experienced greater traumatic brain injury severity. As expected, acute and rehabilitation lengths of stay were longer in the VA with no differences in death rate found between cohorts. Conclusions: Substantial baseline differences between the NIDILRR and VA TBIMS participants warrant caution when comparing rehabilitation outcomes. A substantive number of NIDILRR enrollees had a history of military service (>13%) warranting further focused study. The TBIMS participant data collected across cohorts can be used to help evidence-informed policy for the civilian and military-related healthcare systems.