Seventh, information on our environmental risk factors and alcohol intake were collected retrospectively from adults. Some of our findings could arise solely from retrospective recall bias. For example, subjects may exaggerate the resemblance between their own level of deviant behavior and that of their peers. However, we consider it unlikely that such biases would produce the major findings in this study. In particular, it is difficult to construct a plausible pattern of recall bias that would result in our pattern of interactions. We demonstrated excellent test–retest reliability for our measures. Furthermore, we used a life history calendar in our assessments. This method, designed to capitalize on the structure of autobiographical memory and promote sequential retrieval within memory networks, has been shown to improve substantially the completeness and accuracy of retrospective recall (Freedman et al. 1988; Belli, 1998; Yoshihama et al. 2002; Cook et al. 2003).
