Results indicated that parental knowledge is related to substance use among African American adolescents and that grade and gender modify the strength of this association. First, parental knowledge was associated with lower substance use rates among adolescents. This finding is consistent with previous research that has found associations between parental knowledge and adolescent substance use in African American samples (Bean et al., 2006; DiClemente et al., 2001; Rai et al., 2003; Stanton et al., 2002). Findings varied as a function of type of substance examined (e.g., alcohol use) and whether or not parental knowledge was examined as a time-varying covariate or a mean score at level-2. As a time-varying covariate, increases in parental knowledge were significantly associated with decreases in tobacco, marijuana, other, and any drug use but not with past month alcohol use. In contrast, average parental knowledge at level-2 was associated with lower rates of past month use for all substances at baseline, including alcohol use. Taken together, these findings suggest that higher levels of parental knowledge may reduce initiation of alcohol use (Simons-Morton & Chen, 2005), but that parental knowledge may not influence rates of monthly use once adolescents have already begun experimenting.
