The authors examine the classification of depressive disorders with an
empirically and mathematically based method, cluster analysis. In a sample
of 228 patients from the NIMH Collaborative Study of the Psychobiology of
Depression, clusters were generated by using crossectional symptoms; course
of illness, family history, and treatment variables were used as
independent variables to evaluate the validity of the clusters. The four
clusters identified correspond roughly to severe depressions with
endogenous features, less severe depressions, bipolar depression with
cycling within the episode, and psychotic depressions. This study supports
the Research Diagnostic Criteria and DSM-III approaches to the
classification of depressive disorders.Abstract Teaser