CHICAGO — As many as 20% of the patients at walk-in clinics may be alcoholics, researchers say, so health workers should add two questions to their screening routine: "Have you ever had a drinking problem?" and "When was your last drink?"
A study in Friday's Journal of the American Medical Assn. concluded that the traditional queries of "How much do you drink?" and "How often do you drink?" were less effective in identifying alcoholics later diagnosed with the widely recognized Michigan Alcoholism Screening Test.
"We think they are important questions, but our study indicates they are not particularly helpful in making a diagnosis," said Dr. Michele G. Cyr of Rhode Island Hospital in Providence, R.I., who conducted the study with Dr. Steven A. Wartman of Brown University.
In the study, 232 new patients at the hospital's primary care unit were asked to answer a series of questions that included all four of those under discussion.
Focus on Consequences
The subjects then took the MAST questionnaire, which focuses on drinking behavior and the social, legal and health consequences.
A person scoring five or more is defined as an alcoholic by the MAST. Forty-seven of the research subjects, or 20.3%, scored in that range.
Results were then analyzed to determine the sensitivity, or effectiveness, of the four questions under study.
To the traditional question "How much do you drink?" 22 of the 47 diagnosed alcoholics said they had four or more drinks a day, the level established for the study as an indicator of alcoholism.
The question was assigned a sensitivity of 46.8%, reflecting the percentage of positive answers among the alcoholics.
To the second traditional question "How often do you drink?" 16 of the alcoholics answered "daily," the expected response from alcoholics.
That question was assigned a sensitivity of 34%.
To the new question "Have you ever had a drinking problem?" 33 of the 47 alcoholics said yes, for a sensitivity rating of 70.2%.
To the second new question "When was your last drink?" just 17 said they had drunk alcohol in the preceding 24 hours.
The last question had a relatively low sensitivity of 36.2%.
Most Made Admission
But researchers found that when they combined responses to the two new questions, 43 of the 47 alcoholics had admitted to having a drinking problem or to drinking within the preceding 24 hours or both.
The sensitivity of a positive response to either or both of the new questions was 91.5%.
Cyr noted that the single most sensitive question was the straightforward "Have you ever had a drinking problem?"
"This result was unexpected, since it is generally thought that alcoholics deny or minimize their drinking problems," she said.
While denial may hinder diagnosis, "this difficulty can be compounded if physicians do not ask straightforward questions regarding drinking problems," Cyr said.
But a spokesman for the New York-based National Council on Alcoholism said denial "is very central to alcoholism."
"It seems to be a characteristic to the use of alcohol that people who are impaired or negatively affected by it don't think that they are," said George Marcelle.