Assessing the Attainment Rates of Updated CDC Milestones Using a New Israeli Developmental Scale

OBJECTIVES: Developmental milestones norms are widely used worldwide and are fundamental for early childhood developmental surveillance. We compared a new Israeli evidence-based national developmental scale with the recently updated Centers for Disease Control and Prevention (CDC) checklists. METHODS: We used a cohort of nearly 4.5 million developmental assessments of 758 300 full-term born children aged 0 to 6 years (ALL-FT cohort), who visited maternal child health clinics in Israel for routine developmental surveillance. Among the assessed milestones of 4 developmental domains (gross motor, fine motor, language, and personal-social) we identified milestones that had equivalents on the CDC checklists and assessed the attainment rates of the Israeli children at the ages recommended by the CDC, at which ≥75% of the children would be expected to achieve the milestone. The analysis was repeated on a subgroup of 658 958 children who were considered healthy, typically developing by their birth and growth characteristics (NORMAL-FT cohort). RESULTS: There were 29 milestones, across all developmental domains and assessment ages, whose definitions by both tools were compatible, and could be compared. The attainment rate at the CDC-recommended age was >90% for 22 (76%) and 23 (79%) milestones, and the median attainment rates were 95.2% and 96.3% in the ALL-FT and NORMAL-FT cohorts, respectively. CONCLUSIONS: For almost all comparable milestones of all domains and all ages, children of the Israeli cohorts achieved the milestones earlier than expected by the CDC-defined threshold age. Evidence-based analysis of milestone norms among different populations may enable adjustments of developmental scales and facilitate more personalized developmental surveillance.