The relationship between eligibility criteria for participation in alcoholbrief intervention trials and other alcohol and health-related variables

In clinical trials of brief interventions,for alcohol use, indiriduals typi cally are defined as eligible for tbe research through meeting quantity fre quency (QF) of alcohol consumption criteria, alcohol-related problems crite ria, or both. The purpose of this study was to evaluate preintervention and posttreatment differences among three groups of research participants elig ible for participation in a brief intervention clinical trial by meeting th e AUDIT total score criterion only, the QF criterion only, or both. The par ticipants were 301 men and women 21 years of age or older who presented for medical treatment at one of twelve primary care clinics and were screened for participation in Me clinical trial. Participants completed an assessmen t protocol at preintervention and 1, 3, 6, 9, and 12 months postinterventio n. The analyses showed statistical differences among the three subgroups on three outcome dimensions of alcohol consumption, related consequences and behaviors, and medical complications; for both consumption and complication s, the AUDIT + QF participants showed greater severity than participants in either of the other two groups. For consequences, AUDIT + QF participants scored higher than the QF participants on one variable constituting this di mension. The overall subgroup differences were maintained at six months in the consumption and consequences data. The implications of these findings f or sensitivity of brief intervention trial design, the discovery of patient moderators of intervention effectiveness, and clinical practice are discus sed.