Reliability of self-reported alcohol consumption before and after December

The purpose of this study is to assess the reliability of a self-reported 12-month alcohol measure obtained 1 month before and after December. As part of a larger study involving multiple telephone contacts, this sample consisted of 112 volunteers who drank alcohol at least monthly. During telephone interviews, respondents were asked about their drinking in the last 12 months in November, 1989, and again in January, 1990. The results indicate that the sample reported significantly lower alcohol use during the past year after December. These lower estimates occurred in both the frequency and the average quantity per occasion measures. There were significant reductions in reports of alcohol consumption in the last 12 months after December for the group which was contacted more often (greater than or equal to 7 times during December). The group contacted fewer times (less than or equal to 2 times during December) also reported lower, but not significant, amounts of alcohol consumed after December. These findings indicate that the prevailing idea that reports of last year's typical drinking obtained in January will be overstated because of the holiday season may be unfounded.