Latent factors in measures of rehabilitation outcomes after traumatic brain injury

Abstract

Objectives: To determine whether there is a latent structure among measures used to evaluate rehabilitation outcomes for persons with traumatic brain injury and if the construct of participation is discernible within this structure.

Design: Exploratory factor analyses of 2 cross-sectional cohorts of rehabilitation patients who sustained a traumatic brain injury up to 5 years prior to assessment.

Primary measures: Community Integration Questionnaire (CIQ), Craig Handicap Assessment and Reporting Technique (CHART), Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), and the Satisfaction With Life Scale (SWLS).

Results: Both factor analyses suggested a latent structure composed of 3 factors that were interpreted as representing the Activities and Participation dimensions of the World Health Organization's International Classification of Functioning, Disability and Health (ICF), and a third representing Subjective Well-Being. Low to moderate correlations were found between factors.

Conclusions: The World Health Organization's ICF excludes subjective well-being; however the factor analyses indicate that it is a distinct domain not incorporated into Activities and Participation. The SF-36, CIQ, and CHART can, in combination, evaluate all 3 domains, but not alone. The SF-36 appears to be sensitive to the affective, but not the cognitive, aspect of Subjective Well-Being. A measure of life satisfaction would be a useful supplement to traditional measures of rehabilitation outcome.