Standardized Early Screening era
Nancy Bayley, with the Bayley Scales of Infant Development (1969), established a normed, rapid assessment of infant mental and motor development tailored for pediatric clinics. Frankenburg and Dodds introduced the Denver Developmental Screening Test (DDST) in 1967, a brief, standardized tool that combined direct observation with parental input to flag delays. David Wechsler's preschool and early-child scales, beginning with the WPPSI in 1967, provided reliable, age-appropriate cognitive benchmarks that supported early screening alongside other measures. Together these figures exemplify the era’s emphasis on reliability, short-form administration, and integrated child-centered reporting to create scalable, clinic-ready screening protocols.