Challenges the typical treatment of causal effects in longitudinal data, arguing that models should be conceptualized and tested in ways that directly reflect prior assumptions as to the trait- or state-like nature of the variables. Examples demonstrate that meaningful longitudinal studies of state variables can be conducted without assuming their…

Identifies interaction effects as the defining feature of resilience and resilience research. Maintains that interaction effects are responsible for the unique contributions of this field of study to the understanding of human development. Suggests that the methodological and statistical challenges posed by interaction effects do not, by…

A neurobehavioral maturity assessment which used data from preterm infants was developed. Eight dimensions of neurobehavioral functioning were found to be stable, nonredundant, and developmentally valid. (PCB)

Quantitative growth curve models for estimating individual developmental functions from various types of longitudinal data are discussed in the context of investigator assumptions and research design characteristics. Linear and nonlinear models that estimate growth curves are illustrated, and contrasted when they are fit to speech development…