Descriptions of intervention(s) / exposure
B: Screening (The screening involves patients to complete the 10-item Alcohol Use Disorders Identification Test (AUDIT) at a computer in the waiting area which is connected to the Internet. They also answered questions about the largest amount they consumed in a single episode in the last 4 weeks, the duration of the episode, their age, gender, and ethnicity. It takes 3 minutes.), information leaflet (An educational leaflet providing information on the effects of alcohol and recommended upper limits for low-risk consumption) plus assessment of alcohol use, perceptions of peer drinking norms, and problems 4 weeks later. The assessment involves a 14-day retrospective account of drinks per day, the Alcohol Problems Scale - 14 items, the Academic Role Expectations and Alcohol Scale - 5 items, estimates of others' drinking (7 items) and their height and weight. Median completion time is 11 minutes.
C: Web-based motivational intervention (single-dose); including comparison of patient's drinking with age/gender norms and recommended upper limits. This intervention takes 11 minutes to answer the questions (see above) plus the time required to read the feedback, which we estimate to be 3-5 minutes. Overall, total time is approximately 15 minutes.
D: Web-based motivational intervention (multi-dose); as in C, provided at the commencement of the trial, at 6 months and at 12 months. This intervention takes 15 minutes at baseline and a further 10 minutes four weeks later for assessment and feedback.