 Bayley Scales of Infant Development

The Bayley Scales of Infant and Toddler Development (Bayley-III is the current version; version 4 is due to release September 2019) is a standard series of measurements originally developed by psychologist Nancy Bayley used primarily to assess the development of infants and toddlers, ages 1–42 months.This measure consists of a series of developmental play tasks and takes between 45 – 60 minutes to administer and derives a developmental quotient (DQ) rather than an intelligence quotient (IQ).