Validation of a Single Screening Question for Problem Drinking
STUDY DESIGN: Cross-sectional study.
POPULATION: Adult patients presenting to 3 emergency departments in Boone County, Missouri, for care within 48 hours of an injury.
OUTCOMES MEASURED: The answers to the question were coded as never, more than 12 months ago, 3 to 12 months ago, and within the past 3 months. Problematic drinking was defined as either hazardous drinking (identified by a 29-day retrospective interview) or a past-year alcohol use disorder (defined by questions from the Diagnostic Interview Schedule).
RESULTS: There was a 70% participation rate. Of 2517 interviewed patients: 29% were hazardous drinkers; 20% had a past-year alcohol use disorder; and 35% had either or both. Considering “within the last 3 months” as positive, the sensitivity of the single question was 86%, and the specificity was 86%. In men (n=1432), sensitivity and specificity were 88% and 81%; in women, 83% and 91%. Using the 4 answer options for the question, the area under the receiver-operating characteristic curve was 0.90. Controlling for age, sex, tobacco use, injury severity, and breath alcohol level in logistic regression models changed the findings minimally.
CONCLUSIONS: A single question about the last episode of heavy drinking has clinically useful sensitivity and specificity in detecting hazardous drinking and alcohol use disorders.
Problematic use of alcohol is a major source of morbidity1 and mortality.2 It is also common: 7.4% of adults in the United States meet criteria for a past-year alcohol use disorder,3 and 15.8% have had at least one episode of heavy drinking in the past month.4 In randomized clinical trials, brief interventions in primary care settings have helped 20% of hazardous and harmful drinkers reduce alcohol consumption to safe levels.5,6
In medical practice, however, most individuals who engage in hazardous or harmful drinking go undetected,7 despite the availability of effective screening instruments.8 Major barriers to implementing screening for alcohol problems include a lack of physician familiarity with screening methods7,9 and a lack of time.10 A simple time-efficient instrument could increase the frequency of screening, which could reduce the burden of alcohol-related harm in our society.
Previous research in primary care showed that a single question about the last occasion of heavy drinking had a sensitivity of 62% and a specificity of 93% for detecting patients with either a past-year alcohol use disorder or hazardous drinking in the past month.11 In that study, the question was presented in written form: “On any single occasion during the past 3 months, have you had more than 5 drinks containing alcohol?” In this report, we examine the clinical utility of a revision of that question presented orally with different threshold values for men and women as a screening instrument for problem drinking among injured patients presenting to emergency departments.
Methods
Data for this report were taken from a study of alcohol and injury that was approved by the institutional review board of the University Health Science Center. Interviews were conducted with patients presenting for care to 1 of the 3 hospital emergency departments in Boone County, Missouri, within 48 hours of an acute injury. Patients were eligible for the study if they were aged 18 years or older, able to converse in English, cognitively intact, not in police custody, and if the injury did not occur in a controlled environment (eg, a nursing home or jail where access to alcohol is limited). Research staff trained in the use of the structured interview provided equal coverage of each day of the week and hour of the day. Interviews were conducted from February 1998 through March 2000.
Instruments
After obtaining informed consent, the first question of the structured interview was about tobacco use. The second was, “When was the last time you had more than X drinks in 1 day?” with X = 5 for men and X=4 for women. The answers were coded as never, more than 12 months ago, 3 to 12 months ago, and within the last 3 months. The threshold values were based on empirical work12 and guidelines;13 we set them one drink higher than in the guidelines to balance sensitivity and specificity based on our previous work.11
We defined problem drinking as either past-month hazardous drinking or a past-year alcohol use disorder. We defined hazardous drinking as consumption of more than 4 drinks in 1 day or 14 in 1 week for men, more than 3 in 1 day or 7 in 1 week for women. One drink in the United States contains approximately 11.5 g of ethanol, the amount in 12 oz of beer, 5 oz of wine, or 1.5 oz of liquor. Data for this assessment were from a 29-day retrospective calendar-based review of day-by-day consumption.14 We defined alcohol use disorders (ie, alcohol abuse or dependence) according to the criteria in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV),15 using the alcohol questions in the structured Diagnostic Interview Schedule (DIS).16 Participants were given a breath alcohol test at the end of the interview using the Alco-Sensor IV model breathalyzer (Intoximeters, Inc, St. Louis, Mo).
