Where, With Whom, and How Much Alcohol Is Consumed on Drinking Events Involving Aggression? Event-Level Associations in a Canadian National Survey of University Students Samantha Wells, Ljiljana Mihic, Paul F. Tremblay, Kathryn Graham, and Andre ´e Demers Background: Epidemiological research using event-level data can provide a better understand- ing of the association between alcohol consumption, characteristics of drinking contexts, and the likelihood of aggressive behavior. The present research assessed whether alcohol intake and char- acteristics of the drinking context were associated with the likelihood of aggression within individ- uals across 3 drinking events based on a national sample of university students, taking into account individual characteristics and university level variables. Additionally, we determined whether individual characteristics, particularly drinking pattern, were associated with alcohol- related aggression controlling for drinking event characteristics, and whether relations of aggres- sion to alcohol and drinking contexts differed by gender. Methods: Secondary analyses of the 2004 Canadian Campus Survey (CCS), a national survey of 6,282 university students (41% response rate) at 40 Canadian universities, were conducted. Respondents were asked about their three most recent drinking events, including whether they were in an argument or fight with someone, number of drinks consumed, and characteristics of the drinking context as well as their usual drinking frequency and heavy episodic drinking. We used multi-level analyses to account for the nested structure of the data (i.e., drinking events nested within individuals who were nested within universities). Results: The number of drinks consumed was positively associated with aggression. Drinking contexts found to be positively associated with aggression included being at a party, at a frater- nity ⁄ sorority and ⁄ or residence, at three or more drinking places (versus 1 or 2), and having a partner present whereas having a meal reduced the likelihood of aggression. A significant interac- tion was found between gender and being at a party, with a significant effect found for women but not for men. Conclusions: These results support experimental evidence indicating a direct role of alcohol in aggression and point to characteristics of the drinking context that might be targeted in future prevention initiatives. Key Words: Alcohol, Drinking Contexts, Aggression, Gender, College Students. H EAVY DRINKING AND alcohol-related harm, including aggression, are significant problems on uni- versity and college campuses (Engs and Hanson, 1994; Nich- olson et al., 1998; Perkins, 2002; Syre et al., 1999; Wechsler et al., 1994). A large proportion of university students experi- ence violence, (Fisher and Wilkes, 2003) with at least 50% of violent episodes on campus involving alcohol (see Roark, 1993). A National Institute on Alcohol Abuse and Alcohol- ism (NIAAA) report on college drinking estimated that each year more than 600,000 students in the U.S. are assaulted by students who have been drinking (NIAAA, 2002). Alcohol-related aggression has been conceptualized as resulting from the effects of alcohol, contextual variables, and individual characteristics (Graham et al., 1998a). The main goal of the present study is to better understand the indepen- dent roles of these three factors in explaining aggression among university students. Alcohol and Aggression While a convergence of experimental and epidemiological evidence suggests that alcohol contributes to aggression, con- clusions concerning this association remain tentative because From the Social Prevention and Health Policy Research Depart- ment, Centre for Addiction and Mental Health, (SW, LM, PFT, KG)London, Ontario, Canada; Health and Prevention Social Research Group (GRASP), University of Montreal (AD), Montreal, Canada Received for publication August 15, 2007; accepted November 21, 2007. Reprint requests: Samantha Wells, Ph.D, Scientist, Centre for Addiction and Mental Health, 100 Collip Circle, Suite 200, London, Ontario, Canada, N6G 4X8; Fax: (519) 858-5199; E-mail: swells@ uwo.ca Copyright Ó 2008 by the Research Society on Alcoholism. DOI: 10.1111/j.1530-0277.2007.00596.x Alcoholism: Clinical and Experimental Research Vol. 32, No. 3 March 2008 522 Alcohol Clin Exp Res, Vol. 32, No 3, 2008: pp 522–533