Exploring the Psychometric Properties of the Disablement in the Physically Active Scale Short Form-8 in Adolescents

Abstract

Context: Patient-reported outcomes are widely used in health care. The Disablement in the Physically Active (DPA) Scale Short Form-8 (SF-8) was recently proposed as a valid scale for the physically active population. However, further psychometric testing of the DPA SF-8 has not been completed, and scale structure has not been assessed using a sample of adolescent athletes. Objective: To assess scale structure of the DPA SF-8 in a sample of adolescent high-school athletes. Main Outcome Measure(s): Adolescent athletes (n = 289) completed the DPA SF-8. Confirmatory factor analysis (CFA) was conducted to assess the psychometric properties of the scale. Results: The CFA of the DPA SF-8 indicated that the model exceeded recommended fit indices (Comparative Fit Index = .976, Tucker–Lewis Index = .965, Root Mean Square Error of Approximation = .061, and Bollen’s Incremental Fit Index = .976). All factor loadings were significant and ranged from .62 to .86. Modification indices did not suggest that meaningful cross-loadings were present or additional specifications that could further maximize fit or parsimony. Conclusions: The CFA of the DPA SF-8 met contemporary model fit recommendations in the adolescent athlete population. The results confirmed initial findings supporting the psychometric properties of the DPA SF-8 as well as the uniqueness of the quality-of-life and physical summary factors in an adolescent population. Further research (eg, reliability, invariance between groups, minimal clinically important differences, etc) is warranted to inform scale use in clinical practice and research.