Validation of the work-ability support scale in individuals seeking to return to work after severe acquired brain injury

Abstract

Purpose To assess the reliability and validity of the work-ability support scale (WSS) in a severe traumatic/acquired brain injury (TBI/ABI) population seeking to return to work (RTW). Materials and methods One hundred forty-four clients were enrolled in a vocational rehabilitation (VR) intervention trial through the Brain Injury Rehabilitation Program in New South Wales, Australia. Each client’s primary brain injury clinician and VR provider completed the WSS pre- and post-intervention. Validating measures assessing dysexecutive behavior, disability, participation, and work instability were completed. Several aspects of reliability and validity were evaluated. Results Internal consistency was excellent for Part A (Cronbach’s αs > 0.9) but unacceptably low to questionable for Part B (αs < 0.6). Inter-rater reliability between clinicians and VR providers was generally fair to moderate for Part A (κw < 0.6) and worse for Part B (κw < 0.5), with both slightly improving at post-intervention. Strong support was found for predictive and convergent validity, but not divergent validity. Confirmatory factor analysis indicated a poor fit for Part A, whereas most Part B fit indices met criteria. Conclusions The WSS can play a useful role in assessing return to work (RTW) potential, planning and evaluation after severe TBI/ABI. Training could improve consistency of administration among staff working across health and VR service sectors.