The dimensionality of clinical depression

Responses of 100 significantly depressed psychiatric patients to the sub-scales of the Beck Inventory of Depression were subjected to Maximum Likelihood factor analysis and orthogonal rotation. Results indicated that the inventory measures six meaningful dimensions, and it was concluded that the existing subjective classifications of depressive illness may be too simple. Comparisons with other factor analytical studies indicated that there is a similarity among the factors obtained in different studies, and in particular, that the largest factor appearing in all studies may be identified as a general factor of endogenous depression.