Factorial invariance of child self-report across healthy and chronic health condition groups: A confirmatory factor analysis utilizing the PedsQL™ 4.0 generic core scales

Objectives: The objective of the present study was to examine the factorial invariance of the PedsQL™ 4.0 Generic Core Scales for child self-report across 11,433 children ages 5-18 with chronic health conditions and healthy children. Methods: Multigroup Confirmatory Factor Analysis was performed specifying a five-factor model. Two multigroup structural equation models, one with constrained parameters and the other with unconstrained parameters, were proposed in order to compare the factor loadings across children with chronic health conditions and healthy children. Results: Metric invariance (i.e., equal factor loadings) was demonstrated based on stability of the Comparative Fit Index (CFI) between the two models, and several additional indices of practical fit including the root mean squared error of approximation, the Non-normed Fit Index, and the Parsimony Normed Fit Index. Conclusions: The findings support an equivalent five-factor structure on the PedsQL™ 4.0 Generic Core Scales across healthy and chronic health condition groups. These findings suggest that when differences are found across chronic health condition and healthy groups when utilizing the PedsQL™, these differences are more likely real differences in self-perceived health-related quality of life, rather than differences in interpretation of the PedsQL™ items as a function of health status.