Knowledge about early childhood development is built on the pioneering studies of Arnold Gesell, MD, PhD, during 4 decades of research at the Yale Child Study Center. Gesell, a developmental pediatrician and psychologist, emphasized that young children require structured observations, appropriate toys, and prompts to elicit motor, communicative, personal, social, and adaptive problem-solving competencies.1 This tradition was systematically codified by Nancy Bayley in the United States and by Ruth Griffiths in the United Kingdom.2(pp1-16) Their standardized assessments are periodically renormed, and their updated versions include the Bayley Scales of Infant Development, Third Edition, Battelle Developmental Inventory 2, and Griffiths Mental Development Scales 2.3 These tools have helped developmental professionals understand the dynamic trajectories of children's psychological growth in the preschool years.
Msall ME. Measuring Outcomes After Extreme Prematurity With the Bayley-III Scales of Infant and Toddler DevelopmentA Cautionary Tale From Australia. Arch Pediatr Adolesc Med. 2010;164(4):391–393. doi:10.1001/archpediatrics.2010.25