Agreement between two measures of alcohol consumption

Area of Science:

• * Alcohol consumption research
• * Public health and epidemiology
• * Patient self-reporting methodologies

Background:

• * Accurate measurement of alcohol consumption is crucial for public health interventions.
• * Self-report questionnaires and diaries are common tools, but their comparative accuracy is debated.

Purpose of the Study:

• * To compare the accuracy of the Quantity-Frequency Questionnaire (QF) against a self-report diary for measuring alcohol intake.
• * To evaluate discrepancies in classifying drinkers and estimating consumption levels between the two methods.

Main Methods:

• * 778 general practice patients completed both a QF and a self-report diary.
• * The QF was administered before a clinical consultation.
• * The diary was completed at home within 24 hours of the consultation.

Main Results:

• * The diary significantly overestimated nondrinkers and identified a higher proportion of heavy drinkers compared to the QF.
• * The QF failed to detect 78% of heavy drinkers identified by the diary.
• * Mean weekly alcohol consumption was higher on the diary (10.51 drinks) than the QF (6.87 drinks); this difference was nonlinear and varied by consumption level.

Conclusions:

• * The Quantity-Frequency Questionnaire may underestimate alcohol consumption, particularly heavy drinking, compared to self-report diaries.
• * Findings highlight significant limitations in current self-report measures for alcohol consumption assessment.
• * Methodological choices in self-reporting can substantially impact population estimates of alcohol intake.