Concurrent validity of the Warner Initial Developmental Evaluation of Adaptive and Functional Skills and the Bayley Scales of Infant and Toddler Development, Third Edition.

WIDEA-FS mobility, communication, and social cognition domains are concurrently valid in infants at high-risk for neurodevelopmental disability. Bayley-III motor, language, and cognitive composite scores are concurrently valid in the same group. The WIDEA-FS mobility and communication domains may be most clinically useful in children <30 months.