The latent factor structure of developmental change in early childhood
Abstract
Piaget proposed that development proceeded in stages; morerecently researchers have proposed modular theories in whichdifferent abilities develop on their own timetable. Despite theabundance of theory, there is little empirical work on the struc-ture of developmental changes in early childhood. We inves-tigate this question using a large dataset of parent-reporteddevelopmental milestones. We compare a variety of factor-analytic item response theory models and find that variationin development from birth to 55 months of age is best de-scribed by a model with three distinct dimensions. We alsofind evidence that dimensionality increases across age, withthe youngest children described by a two-factor model. Theseresults provide a model-based method for linking holistic de-scriptions of early development to basic theoretical questionsabout the nature of change in childhood.