A Second-Order Growth Mixture Model for Developmental Research

Abstract
Growth mixture modeling, a combination of growth modeling and finite mixture modeling, is a flexible, exploratory method for identifying and describing between-person heterogeneity in change. In this article we introduce a second-order growth mixture model that combines a longitudinal common factor model, measurement invariance constraints, latent growth model, and mixture model. This approach capitalizes on the benefits of multivariate measurement and the flexibility of mixtures for representing heterogeneity. We describe the model and illustrate its use with multi-reporter longitudinal data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development tracking the development of children's externalizing behaviors through elementary school.