Concurrent Validity of the Bayley Scales of Infant Development II Motor Scale and the Peabody Developmental Motor Scales-2 in Children with Developmental Delays

Abstract

The study supports concurrent validity of the tests only for certain subscale age-equivalent scores, particularly the BSID II Motor Scale with the PDMS-2 Locomotion Subscale. The current findings suggest that the standard scores show poor agreement and have low concurrent validity. There are marked differences in the standard scores of the two tests that may affect a child's eligibility for services in some states, and therapists should be cautious when making clinical decisions based solely on standard scores of one test.