AUDIT-C, which includes only the first three (quantity and frequency) questions of the AUDIT, is a practical, valid, primary care screening test for heavy drinking and/or active alcohol abuse or dependence. Developed using questionnaire and telephone interview data from 243 patients at three Veterans Affairs (VA) general medical clinics (Bush et al., 1998a), it has become the most popular short version of the AUDIT. The three-item AUDIT-C demonstrated greater accuracy for heavy drinking than the full AUDIT and performed similarly in detecting heavy drinking and/or active alcohol abuse or dependence (Bush et al., 1998a). Since 2007, the AUDIT-C has been a required annual screening test in primary care in the Veterans Affairs Health System (VAHS), where it has high sensitivity and specificity for alcohol use disorders (Barnes et al., 2010, McGinnis et al., 2013). Although the AUDIT-C is widely used, inaccurate reporting could limit its utility in identifying AD genetic variants. In contrast, an alcohol biomarker should provide an unbiased estimate, but is not readily available in large samples.
