Concordance of adolescent reports of friend alcohol use, smoking, and deviant behavior as predicted by quality of relationship and demographic variables.

OBJECTIVE: The strongest predictor of adolescent alcohol use is affiliation with friends who drink, use other drugs, or engage in deviant behavior. Most studies measure this variable using adolescent perceptions of friend problem behavior, but some research suggests these perceptions may be inaccurate. The current study's objective was to determine the concordance between adolescent perceptions of their friend's drinking, smoking, and deviant behavior and the friend's self-report. Relationship characteristics and demographic variables were explored as predictors of report concordance.
METHOD: Participants (targets) were 232 adolescents ages 13 or 15 (53% girls) from Wave 9 of the Tween to Teen Project. At least one reciprocally endorsed friend participated for 59% of target adolescents (n = 232/390). Targets completed computer-assisted interviews. Friends completed telephone interviews.
RESULTS: The relations between target perceptions of friend and friend self-reports of drinking and smoking were statistically significant (p < .001), but concordance was driven largely by agreement regarding the absence of behavior. Although 22% of friends drank and 8.6% smoked, fewer than 60% of targets perceived these behaviors. Deviant behavior reports correlated moderately (r = .45), with 51% of adolescents underreporting friend deviance. There were few predictors of report concordance.
CONCLUSIONS: Adolescents and their friends generally provided concordant reports of one another's drinking and smoking behaviors, but most agreement concerned the absence of behavior; most targets provided underreports of their friend's engagement in deviant behaviors. These findings suggest that adolescent perceptions of friends' problem behavior do not exaggerate the involvement of their friends in these behaviors.