Conjoint screening questionnaires for alcohol and other drug abuse: criterion validity in a primary care practice

The US Preventive Services Task Force recommended that physicians use the CAGE questions to screen patients for alcohol abuse. A similarly brief screening instrument for abuse of other drugs is needed. Two conjoint screening questionnaires for alcohol and other drug abuse were adapted from the CAGE questions and the Short Michigan Alcoholism Screening Test (SMAST). For 124 patients of an academic, community family practice, the conjoint questionnaires and their forerunners were compared with DSM-III-R diagnoses of substance use disorders as measured by the Diagnostic Interview Schedule-Revised (DIS-R). The SMAST and its conjoint analog exhibited low sensitivity. The CAGE Adapted to Include Drugs (CAGE-AID) was more sensitive but less specific for substance abuse than the CAGE, especially when a reduced criterion score was employed. The CAGE-AID was more sensitive than the CAGE for subjects of varying sex, income, and level of education, as well as most patterns of substance use disorders. The diminished specificity of the CAGE-AID may have been, at least in part, artifactual. The CAGE-AID holds promise for identifying primary care patients with alcohol and drug disorders.