We rely on retrospective reports, though the use of a life history calendar has been shown to mitigate problems with accurate recollection. Variation in age at interview potentially introduces bias into the accuracy of recall; however, tests wherein age at interview was included as a covariate resulted in the same model structure presented here. We are also limited to self-reports, which might be subject to bias. Similarly, some evidence suggests that self-reports of peer behavior overestimate the similarity between one’s own behavior and that of their peers (Hill et al., 2008). Data were only available for men, and there is potential for gender differences in the role of peer influences on drinking (Dick et al., 2007).
