What Is Moderate Drinking?

Alcohol Research & Health, Wntr, 1999 by Mary C. Dufour

Despite the limitations of self-reports, studies examining the reliability and validity of survey measures of alcohol consumption have indicated high levels of reliability - that is, when asked more than once, people generally are consistent in how much alcohol they report using. In fact, in nutritional epidemiology studies that investigated the consumption of various food categories, reported alcohol intake was particularly reproducible compared with the reported intake of other nutrients (Longnecker et al. 1993). Validity estimates (i.e., estimates of whether the survey measures actually provide accurate information on drinking levels) are not always as high as reliability estimates, but they generally fall within the upper range of the validity estimates of many comparable research projects (Williams et al. 1985).

For some analyses, such as studies investigating drinking consequences (e.g., drinking and driving and other alcohol-related injuries and violence) not only the amount but also the pattern of alcohol consumption is important and should be assessed. For example, imagine two people who consume identical average volumes of alcohol (e.g., 14 drinks per week). One person consumes 2 drinks each evening, whereas the other person ingests all 14 drinks within a few hours on a Saturday night. That difference in drinking pattern has considerable implications for the drinkers with respect to the likelihood of experiencing negative outcomes, such as alcohol poisoning or alcohol-related traffic crashes. Unfortunately, little consensus exists among scientists as to what constitutes hazardous drinking and how one can best measure drinking patterns in general and hazardous drinking patterns in particular. Researchers have developed several definitions of hazardous drinking, such as consumption of five or more drinks on one drinking occasion or being intoxicated more than a certain number of times in a given time period. Few studies, however, have compared the ability of those various definitions to predict alcohol-related outcomes or their usefulness in shaping public health policy.

WHAT IS MODERATE DRINKING?

Not surprisingly, given the variability in the definitions of one drink, the numerous approaches to assessing alcohol consumption, and the subjective interpretation of the word "moderate," definitions of "moderate drinking" vary considerably among researchers. In the English language, "moderate" can be used as both a qualitative and a quantitative term, but it generally carries strong qualitative connotations. For example, Webster's dictionary (1966) defines moderate as "characterized by an avoidance of extremes of behavior; observing reasonable limits, showing discretion and self control" (p. 1451). based on this definition, most people who consume alcohol would likely consider themselves moderate drinkers, regardless of the actual alcohol amounts they consume.

Despite the rather vague definition of "moderate," alcohol survey researchers use the term to describe certain drinking levels. In their surveys, scientists must classify the wide range of alcohol consumption found in the population (e.g., from zero to more than 20 drinks per day) into a manageable number of drinking categories. One commonly used scheme includes the categories of abstainer, light drinker, moderate drinker, and heavy or heavier drinker. The definitions of each category, however, can vary among studies. For example, Dawson and colleagues (1995) proposed the following definitions, where one drink is equivalent to 0.5 fl oz alcohol: