Comparing the BDI-II and the PHQ-9 with outpatient substance abusers.

Because of the high co-occurrence of Axis-I mood disorders with primary substance use disorders (SUD), it is important to routinely assess substance abusers for evidence of a mood disorder. The primary goal of the present study was to examine the psychometric characteristics of two widely used self-report measures of depression (Beck Depression Inventory-II; Patient Health Questionnaire PRIME MD) with substance abusers (N=108) in an outpatient treatment setting. Using Cronbach's alpha, the reliabilities of the BDI-II and the PHQ-9 were 0.95 and 0.91, respectively. Principal component factor analyses of both measures were conducted to evaluate the relationship between a 3-factor solution (cognitive, affective, and somatic) for the BDI-II and a 1-factor solution for the PHQ-9 (depression). Both measures were correlated with severity levels of alcohol and drug use. Advantages and disadvantages of using both measures with substance abusers are discussed.