If the AUDIT is used as a standard to detect hazardous drinkers, would the AUDIT-C or AUDIT-3 identify the same patients as the full AUDIT? Using cutoff points for the AUDIT-C of 3 or higher and an AUDIT-3 score of 1 or higher, these instruments were 99.7% and 98.3% as sensitive as the full AUDIT. As expected, specificity is much less for both abbreviated instruments. However, the high sensitivity suggests a clinical utility for these abbreviated instruments. It is unlikely that by asking the 3 AUDIT-C questions or the single AUDIT-3 question, a primary care provider will miss identification of a person who is at least a hazardous drinker.
Limitations
There is no gold standard to identify hazardous drinkers.41 The definition of what level of drinking constitutes that label is controversial, and providers do not routinely ask standard questions about drinking behavior.16 Our criterion, the quantity-frequency questions, may be considered a poor standard to compare survey instruments.7,42 In research, quantity-frequency consumption questions are helpful in specific identification of hazardous drinkers when a cutoff value is defined.5 However, patients may prefer not to answer questions about quantity or frequency of alcohol use and may not respond consistently to heterogeneous provider questions. Therefore, quantity-frequency questions may be useful as a standard to compare similar instruments such as the AUDIT and its abbreviations, although they may not be particularly effective in clinical practice.
Not all surveyed individuals completed the full AUDIT instrument. This was primarily because patients who answered “never” to our initial question regarding any alcohol use did not proceed to the AUDIT. Before completion of the study, we eliminated this question from the survey. However, it is not known whether patients who answered “never” to the initial question, were, in fact, drinkers. Consistency response bias may also have occurred as patients may have wished to answer similar items similarly. In addition, the similarity of the AUDIT-C and AUDIT-3 to quantity-frequency questions suggests that our sensitivity analysis is perhaps only the upper bounds of the briefer instruments.
We derived the abbreviated tests directly from the AUDIT, thus no assessment of the instruments out of the context of the full AUDIT was performed. Independent testing of abbreviated AUDIT instruments is needed. Recruitment was conducted by research assistants who solicited and provided forms to patients in the waiting rooms of primary care clinics. This convenience sample may have led to a selection bias in obtaining survey data. Patient recall bias may also have affected survey answers as patients may have had difficulty answering quantity and frequency questions accurately (an advantage of the AUDIT over quantity-frequency type questions). Also, our study investigates identification of individuals who are at least hazardous drinkers, but may also be abusive or dependent. We did not study the instruments’ ability to distinguish between hazardous drinking and abuse or dependence.
Conclusions
Our results confirm that the AUDIT-C and AUDIT-3 are useful screening tests for hazardous drinking. Because treatment of such drinkers can be effective, identifying people with less severe alcohol problems is crucial and an important public health initiative.21 Abbreviated instruments identify hazardous drinkers quickly, efficiently, and effectively, and may encourage early treatment to prevent the occurrence of alcohol-related consequences, abuse, or dependence. We recommend using the AUDIT-C and CAGE as brief screening instruments for hazardous drinking and alcohol abuse and dependence. This approach warrants further investigation.
Acknowledgments
Our work was supported by a grant to Dr Maisto from the National Institute of Alcohol Abuse and Alcoholism (AA10291). Dr Gordon is supported by a faculty development grant in general internal medicine from the VA Pittsburgh Healthcare System and the VISN 4 Mental Illness Research, Education, and Clinical Center. Dr Kraemer is supported by a Mentored Clinical Scientist Development Award from the National Institute of Alcohol Abuse and Alcoholism (AA00235). Dr J. Conigliaro is supported by a Career Development Award from the HSR & D Service, Department of Veterans Affairs (CD-97324-A) and is a generalist physician faculty scholar of the Robert Wood Johnson Foundation (#031500). We thank the ELM research study staff, Monica O’Connor (the ELM project coordinator), and all the patients who participated in the ELM study.