Convergent and known-groups validity of the Pediatric Evaluation of Disability Inventory - Patient-Reported Outcome...

The availability of psychometrically sound patient-reported outcome measures for youth and young adults (YYA) with intellectual and developmental disabilities is an issue of justice. This study investigated the convergent and known-groups validity of the Pediatric Evaluation of Disability Inventory - Patient-Reported Outcome (PEDI-PRO) using similar measures of functional performance: the Pediatric Evaluation of Disability Inventory - Computer Adaptive Test (PEDI-CAT) and the Adaptive Behavior Assessment System (ABAS-3).

YYA (n = 306), ages 14-22 with intellectual and developmental disabilities, were eligible for this study. Subsamples were created to optimize power for each analysis; 263 YYA had PEDI-CAT scores, 279 YYA had ABAS-3 scores, and 122 YYA had verified IQ scores.

There were significant correlations between PEDI-PRO and PEDI-CAT domains (p < 0.001 for all): Daily activities (moderate); Social/Cognitive and Mobility (small). There were significant differences in PEDI-PRO scores for YAA with higher and lower scores on proxy-reported measures: intellectual function, self-care adaptive skills, communication and social adaptive skills, and mobility.

Results provide evidence for the PEDI-PRO's ability to distinguish between YYA with higher and lower abilities, and provide unique yet complimentary information from that provided by parents and teachers.