Conceptual Structure of Health Related Quality of Life for Persons with Traumatic Brain Injury: Confirmatory Factor Analysis of the TBI-QOL

Abstract Objective To determine the factor structure of the Traumatic Brain Injury – Quality of Life (TBI-QOL) measurement system. Design Observational. Setting 3 TBI Model Systems rehabilitation centers in the US Participants and Methods: 20 TBI-QOL item banks were administered to a sample of 504 community-dwelling adults with traumatic brain injury (TBI) as part of a study of TBI classification. A subsample of n=200 participants was randomly selected for exploratory factor analyses (EFA), while data from the remaining 304 participants were used for the confirmatory factor analysis (CFA). To examine a wide range of conceptual models, CFA were conducted on a total of 16 models, ranging from 1 to 7 factors. Results Initial EFA yielded support for a 5-factor model (negative emotion, cognitive impairment, functioning and participation, positive emotion, and pain). CFA results; however, indicated a 7-factor model including: physical function, physical symptoms, cognition, negative emotion, positive emotion, sense of self, and social participation (Model 16; Robust Fit Statistics RMSEA=0.063, SRMR=0.035, CFI=0.955, TLI=0.943, and BIC=40059.44). Conclusions The complex 7-factor model of the TBI-QOL provides a more nuanced framework for understanding health related quality of life for persons with TBI than the commonly used 3 factor model including physical health, mental health, and social health.