Predicting 18-month M-CHAT-R/F With PediaTracTMv3.0 Motor and Social/Communication/Cognition Domains

PURPOSE: This study examined whether caregiver-reported indices of motor and social/communication/cognition in infancy could predict the likelihood of autism spectrum disorder (ASD) at 18 months, as measured by the Modified Checklist for Autism in Toddlers, Revised with Follow-Up (M-CHAT-R/F). METHODS: Participants included 415 caregiver-infant dyads (45% female; 170 preterm) from the longitudinal PediaTrac™ v3.0 study that tracked infant and toddler development from birth to 18 months. Cross-sectional latent traits of motor (MOT) and social/communication/cognition (SCG) ability at 9 and 12 months and longitudinal trajectory parameters from birth to 12 months served as predictor variables of later ASD likelihood. Hierarchical multiple regression models examined whether cross-sectional abilities or longitudinal trajectories better predicted M-CHAT-R/F scores at 18 months, controlling for preterm status × male sex, maternal education, maternal age, and Area Deprivation Index. RESULTS: Longitudinal trajectories accounted for greater variance in M-CHAT-R/F scores than cross-sectional measures. Lower developmental slopes in MOT and SCG predicted higher autism likelihood scores at 18 months, and higher neighborhood socioeconomic disadvantage was the most robust predictor of later ASD likelihood (among all variables in this study). CONCLUSION: Findings support PediaTrac's validity as a caregiver-reported measure for identifying early developmental patterns linked to later autism likelihood. Integrating developmental trajectories with socioeconomic contextual factors would improve early detection and guide intervention development.