An experimental test of assessment reactivity within a web-based brief alcohol intervention study for college students

• No significant reactivity effects from online assessments combined with an alcohol intervention
• Online assessments did not inflate intervention efficacy estimates measured within-subjects.
• Findings indicate universities may observe intervention effects similar to efficacy studies.

ObjectiveWeb-based brief alcohol intervention (WBI) programs have efficacy in a wide range of college students and have been widely disseminated to universities to address heavy alcohol use. In the majority of efficacy studies, web-based research assessments were conducted before the intervention. Web-based research assessments may elicit reactivity, which could inflate estimates of WBI efficacy. The current study tested whether web-based research assessments conducted in combination with a WBI had additive effects on alcohol use outcomes, compared to a WBI only.MethodsUndergraduate students (n = 856) from universities in the United States and Canada participated in this online study. Eligible individuals were randomized to complete 1) research assessments + WBI or 2) WBI-only. Alcohol consumption, alcohol-related problems, and protective behaviors were assessed at one-month follow up.ResultsMultiple regression using 20 multiply imputed datasets indicated that there were no significant differences at follow up in alcohol use, alcohol-related problems, or protective behaviors used when controlling for variables with theoretical and statistical relevance. A repeated measures analysis of covariance revealed a significant decrease in peak estimated blood alcohol concentration in both groups, but no differential effects by randomized group. There were no significant moderating effects from gender, hazardous alcohol use, or motivation to change drinking.ConclusionsWeb-based research assessments combined with a web-based alcohol intervention did not inflate estimates of intervention efficacy when measured within-subjects. Our findings suggest universities may be observing intervention effects similar to those cited in efficacy studies, although effectiveness trials are needed.