The longitudinal structure of the Children's Depression Inventory: testing a latent trait-state model.

In a 6-wave longitudinal study, children (Grades 4-6, n = 648), adolescents (Grades 7-9, n = 1,489), and their parents completed child-adolescent or parent versions of the Children's Depression Inventory (CDI; M. Kovacs, 1981). Using structural equation modeling, the authors conducted latent trait-state analyses to distinguish between a stable trait dimension of depression (in which individual differences are stable over time) and an autoregressive dimension (in which individual differences are less stable over time). Children's CDIs reflected the autoregressive dimension more than a stable trait dimension, whereas parents' CDIs reflected a stable trait dimension more than an autoregressive dimension. Reports from adolescents and their parents reflected a stable trait dimension more than an autoregressive dimension of depressive symptoms. Results suggest that the longitudinal structure of the CDI varies considerably depending on the age of the target and the type of informant.