All alcohol exposure counts - testing parental, older sibling, best friend and peer exposure on young adolescent...

Role models around the adolescent, including parents, peers, best friends and older siblings, all act in ways to socialize the adolescent into alcohol use. This study aims to examine the effect of exposure to siblings' drinking alongside the more traditionally examined role models on alcohol use among adolescents.

A longitudinal study followed adolescents (45.6% male) who completed a questionnaire every 6 months over 3 years (seven in total).

Netherlands PARTICIPANTS: This resulted in 5112 observations clustered in 765 participants aged between 10 and 16 years.

We examined three alcohol use measures: alcohol use in the last 6 months, in the last 4 weeks and binge drinking in the last 4 weeks-both cross-sectionally at each time-point and their change from one time-point to the next in a series of multi-level logistic regression models.

Results revealed a non-significant difference in any of the exposure or alcohol use variables between those with or without older siblings. Higher exposure to sibling drinking was significantly associated with all alcohol use outcomes: use in the last 6 months, odds ratio (OR) = 1.54, 95% confidence interval (CI) = 1.25-1.91; last 4 weeks, OR = 2.04, 95% CI = 1.60-2.60; and binge drinking, OR = 2.35, 95% CI = 1.82-3.05. When adding the other role models (i.e. peers, mothers, fathers and best friends), the significant association between siblings' exposure and adolescents' alcohol use remains.

It would appear that, after adjustment for the effect of role models, adolescents who are exposed to more sibling drinking are more likely to have drunk alcohol during the past 6 months and past 4 weeks and also to binge drink.