of the sample had experienced sexual debut before age 18, which means that a high school diploma would not be an appropriate predictor of sexual debut. Because of the ascertainment procedures, we did not know which comparison participants had a biological alcohol dependent second-degree relative (e.g., aunt, uncle, or grandparent). In addition, we relied on participants' self-report for all of the data. Self-report data are subject to response bias such as social desirability, recall bias, and reporter bias (Hardt & Rutter, 2004; Henry, Moffit, Caspi, Langley, & Silva, 1994; Huang, Liao, & Chang, 1998; Sales, Milhausen, & Diclemente, 2006). Due to the cross-sectional and non-experimental design of our study, we are unable to make any definitive conclusions about the direction and nature of relationships. Because participants were not asked whether first intercourse occurred in the context of drinking, we cannot be certain if alcohol directly affected such behavior.
