Correlates of alcohol consumption on heavy drinking occasions of young risky drinkers: event versus personal characteristics

Aims Risky single‐occasion drinking (RSOD) by young people is a serious public health issue, yet little is known about the specific circumstances of risky drinking occasions. This study examined the independent effects of event‐ and individual‐specific variables on RSOD. Design Longitudinal cohort study measuring self‐reported RSOD and event‐ and individual‐specific variables across two drinking occasions approximately 1 year apart. Setting Metropolitan Melbourne, Australia. Participants A sample of 710 young risky drinkers aged between 18 and 25 years and defined as engaging in risky drinking practices (males: consumed alcohol in excess of 10 Australian Standard Drinks (ASD: 10 g ethanol) in a single occasion in the previous year; females: consumed alcohol in excess of seven ASD for females in a single occasion in the previous year). Measurements Random digit‐dial telephone landline survey of the most recent heavy drinking occasion and socio‐demographic variables. The primary outcome was the log of the total drinks consumed in the most recent heavy drinking occasion. Event‐specific (e.g. number of drinking locations) and time‐varying (e.g. weekly income) and time‐invariant (e.g. sex) individual‐specific variables were examined as correlates of total drinks consumed. Findings Changes in event‐specific characteristics including the length of the drinking occasion (Likelihood Ratio χ2(2) = 24.4, P