Assessing depression in drug- and alcohol-dependent subjects: the utility of a cognitive-based approach

Our objective was to report the development of a measure designed to assess depression severity in those with drug and or alcohol problems not confounded by somatic items that may more reflect the impact of drug and alcohol problems rather than depression itself. A questionnaire was derived with 49 items, each assessing cognitive aspects of depression. Subjects with drug and or alcohol problems completed the measure and a standard self-report depression inventory and were assessed for depression presence and severity by a psychiatrist, who used a structured case-finding measure to complement a semi-structured clinical assessment. A high percentage of the sample was found to be depressed. Total scores on the new measure correlated highly with scores on the two other depression reference measures, supporting its validity as a measure of depression severity. A refined set of 14 items was also identified as a valid measure of depression severity, whereas a determined cut-off established high assignment accuracy when examined against the clinical judgement of caseness. In conclusion, the refined 14-item set has been validated as a depression measure in those with drug and alcohol disorders, whereas the item content may assist clinicians to frame screening questions in assessing such patients.