Construct validity of the comprehensive developmental inventory for infants and toddlers

Background: The aim of this study was to investigate the construct validity of the diagnostic test, the Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT). Methods: A total of 1085 children in four age groups (infant, 1-year-old, 2-year-old, preschool age) were enrolled. The Developmental Quotient of each subdomain of the five CDIIT subtests (Cognition, Language, Motor, Social, and Self-help) was used as the basic unit for factor analysis with the iterative principle factor method and promax rotation. Results: The two-factor solution in two younger age groups and 2- or 3-factor solutions in the 2-year-old and preschool groups provided superior factor structure in terms of interpretability and compatibility with existing child development theories. Conclusion: Although five constructs were proposed in the original manual of CDIIT, two to three constructs were revealed in this empirical study.