Accuracy and precision of the Pediatric Evaluation of Disability Inventory computer-adaptive tests (PEDI-CAT)

Abstract

Aim: The aims of the study were to: (1) build new item banks for a revised version of the Pediatric Evaluation of Disability Inventory (PEDI) with four content domains: daily activities, mobility, social/cognitive, and responsibility; and (2) use post-hoc simulations based on the combined normative and disability calibration samples to assess the accuracy and precision of the PEDI computer-adaptive tests (PEDI-CAT) compared with the administration of all items.

Method: Parents of typically developing children (n = 2205) and parents of children and adolescents with disabilities (n = 703) between the ages of 0 and 21 years, stratified by age and sex, participated by responding to PEDI-CAT surveys through an existing Internet opt-in survey panel in the USA and by computer tablets in clinical sites.

Results: Confirmatory factor analyses supported four unidimensional content domains. Scores using the real data post hoc demonstrated excellent accuracy (intraclass correlation coefficients ≥ 0.95) with the full item banks. Simulations using item parameter estimates demonstrated relatively small bias in the 10-item and 15-item CAT versions; error was generally higher at the scale extremes.

Interpretation: These results suggest the PEDI-CAT can be an accurate and precise assessment of children's daily performance at all functional levels.

Conflict of interest statement

Conflict of Interest Statement: Dr. Haley and Mr. Moed own founders stock in CRECare, LLC, which distributes the PEDI-CAT products.

© The Authors. Developmental Medicine & Child Neurology © 2011 Mac Keith Press.

Figures

Figure 1

Comparison of Full Item Bank and RMSE Conditioned on PEDI-CAT Score