Abstract
Motor skill is foundational for early development and an important indicator of whether children's development is on track. The NIH "Baby" Toolbox®, an iPad-based app designed for broad use by nonexperts, includes measures to assess motor skill in children aged 16 days to 42 months. The measures use direct observation in functional, everyday, child-friendly tasks-reaching to eat and getting up to go to a caregiver-to assess children's manual, postural, and locomotor skills. Administration and scoring uniquely capitalize on the video capabilities of the iPad to allow instantaneous review of fast, subtle movements and comparison to standard exemplar illustrations. Moreover, videos can be exported for later analysis and reuse. A large-scale norming study (N = 2353; 1921 English-speaking, 432 Spanish-speaking) verified the reliability and validity of the Reach to Eat and Get Up and Go measures. An additional supplementary measure, Sit and Stand, is designed to assess stationary postural control, akin to the Standing Balance measure in the NIH Toolbox for older children and adults. Findings support the Baby Toolbox as a reliable, valid, scalable assessment instrument for infant and toddler fine and gross motor skill.