A proposal for a dimensional classification system based on the shared features of the DSM-IV anxiety and mood disorders: Implications for assessment and treatment.

A wealth of evidence attests to the extensive current and lifetime diagnostic comorbidity of the Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV) anxiety and mood disorders. Research has shown that the considerable cross-sectional covariation of DSM-IV emotional disorders is accounted for by common higher order dimensions such as neuroticism/behavioral inhibition (N/BI) and low positive affect/behavioral activation. Longitudinal studies indicate that the temporal covariation of these disorders can be explained by changes in N/BI and, in some cases, initial levels of N/BI are predictive of the temporal course of emotional disorders. The marked phenotypal overlap of the DSM-IV anxiety and…