EXAMINING PREVALENCE DIFFERENCES IN THREE NATIONAL SURVEYS OF YOUTH: IMPACT OF CONSENT PROCEDURES, MODE, AND EDITING RULES

We examined the potential prevalence impact of differences in consent procedures, mode of administration, and editing protocols in the 1997 National Household Survey on Drug Abuse, the Monitoring the Future study, and the Youth Risk Behavior Survey, limiting analyses to 10th and 12th graders. NHSDA's high level of compliance with federal regulations regarding human subjects research, including thorough parental permission prior to adolescent participation, may in part be responsible for the relatively low prevalence rates obtained in this study. Key mode effects which contribute to observed differences across surveys are survey setting and privacy. The two school-based surveys produce higher prevalence estimates than the NHSDA. Although NHSDA prevalence rates increase with increased interview privacy, the increase is not enough to account for discrepancies with the school surveys. The procedures used to handle inconsistent survey responses and to impute missing data are very different across the three surveys. These differences in editing procedures, however, are unlikely to be responsible for the observed differences in prevalence rates. Based on these analyses, we conclude that the field would benefit from a well-designed experimental study evaluating school vs. household effects as well as the impact of variation in consent procedures. Increased methodological research on the validity of school based drug surveys is also needed.