The latent structure of child depression: a taxometric analysis. 
The current study examined the categorical versus continuous nature of child and adolescent depression among three samples of children and adolescents ranging from 5 to 19 years.  Depression was measured using the Children's Depression Inventory (CDI).  Indicators derived from the CDI were based on factor analytic research on the CDI and included indices of: 1) social withdrawal, 2) anhedonia, 3) incompetence/maladjustment and 4) negative self-esteem.  Taxometric procedures provided convergent support for the existence of a latent taxon across three independent samples.  Internal and external consistency tests as well as Monte Carlo simulations supported the validity of the results.  Multiple nonredundant procedures and samples were all consistently indicative of taxonicity in child depression.