Journal of Consulting and Clinical Psychology
Objective: While college alcohol misuse remains a pervasive issue, individual-level interventions are among the most efficacious methodologies to reduce alcohol-related harms. Growth mixture modeling (GMM) was used as an exploratory moderation analysis to determine how many types of college drinkers exist with regard to intervention efficacy over a 12-month period.
Method: Data from 3 randomized controlled trials were combined to yield a sample of 1,040 volunteer and mandated college students who were given 1 of 3 interventions: a brief motivational intervention, Alcohol Edu for Sanctions, or Alcohol 101 Plus. Participants were assessed at baseline, and 1, 6, and 12 months post intervention.
Results: Through the examination of heavy drinking behaviors, piecewise GMM identified 6 subpopulations of drinkers. Most of the sample (76%) was lighter drinkers who demonstrated a strong intervention response, but returned to baseline behaviors over the subsequent 12 months. In contrast, 11% of the sample reported no significant change over the 12-month period. Four minority subpopulations were also identified. In sum, 82% of the sample responded to intervention, but 84% of the sample reported intervention decay over the subsequent 12 months. Female gender, being an, upperclassmen, beginning drinking later in life, not engaging in drinking games, and lower norms predicted a greater likelihood of responding to intervention.
Conclusion: Individual-level interventions are successful at effecting change in most college students, but these effects tend to decay to baseline behaviors by 12 months. These results suggest intervention efforts need to find ways to engage freshmen men and those who play drinking games.
Public Health Significance: This study suggests that there are distinct subgroups of college students defined by how they respond to alcohol intervention, and that interventions need to target freshmen men and those who play drinking games. Although most students initially response to intervention effects, most also show intervention decay over the next 12 months, which suggests that we need to determine ways of improving the long-term effects of alcohol interventions.
Original Publication Citation
Henson, J. M., Pearson, M. R., & Carey, K. B. (2015). Defining and characterizing differences in college alcohol intervention efficacy: A growth mixture modeling application. Journal of Consulting and Clinical Psychology, 83(2), 370-381. doi:10.1037/a0038897
Henson, James M.; Pearson, Matthew R.; and Carey, Kate B., "Defining and Characterizing Differences in College Alcohol Intervention Efficacy: A Growth Mixture Modeling Application" (2015). Psychology Faculty Publications. 67.