Ways of measuring drinking patterns and the difference they make: experience with graduated frequencies.

This paper reviews methodological issues in assessing volume and pattern of alcohol consumption. It focuses on three measures developed at the Alcohol Research Group (ARG) to assess frequencies of drinking in a graduated series of quantity intervals, called the graduated quantity-frequency (QF) approach. The three measures include two reference periods, 30 days and 12 months, and use three distinct ways of assembling the graduated QF data. The Cahalan-Treiman 30-day measure, developed for self-administered mail surveys, targets daily amounts of beverage alcohol, with thresholds asked in ascending order. The other two measures use descending quantity ranges. The Knupfer Series (KS) asks for three beverage-specific quantity levels. The Graduated Frequencies (GF) measure assesses intake of combined alcohol with five levels. Both are available in face-to-face and telephone formats. All three measures inquire about consumption in the metric of "drinks," defined within the form or interview; each is useful for estimating volume and pattern of consumption. Methodological studies with the GF include comparisons with other measures, between- and within-subject interview comparisons, and qualitative protocol analyses designed to examine cognitive response processes. Uses for each measure are considered, and recommendations are made for improvement and more thorough specification of drinking patterns.