The resulting study sample includes 2,501 youth, enrolled over a three-year period from fall 1999 through fall 2001 (Table III.1; top panel). Within each program site, sample sizes ranged from 504 for FUPTP to 849 for Teens in Control. Just less than 60 percent of the study sample was assigned to the program group (1,461); the remainder was assigned to the control group (1,040).
|My Choice, My Future!
|ReCapturing the Vision
|Teens in Control
|Number in Study Sample|
|Response Rate on Final Follow-Up Survey|
|Sample Size for this Report
(Number in Study Sample x Response Rate)
|Source: Tracking system for the Survey of Teen Activities and Attitudes (Mathematica Policy Research, Inc., 1999 and 2000) administered to youth in the Title V, Section 510 Abstinence Education Program study sample.|
Data were collected from the study sample through a series of four surveys.(1) They included a baseline survey, administered near the time that youth began participating in the study, and three follow-up surveys. The surveys were administered either in school using a pen-and-paper instrument or by phone.
The impact findings presented in this report are based on data collected from the final follow-up survey, which was administered to study youth between spring 2005 and winter 2006. This reflects a follow-up period of roughly 42 to 78 months after youth began participating in the study, depending on the year in which they began participating and the exact timing of the survey. The response rate on this survey ranged from 80 to 84 percent across the four study sites, leading to an 82 percent rate overall (Table III.1, middle panel).
In each site, the sample size available for this report is given by the product of the number of youth in the study sample (upper panel of Table III.1) and their corresponding response rate on the final follow-up survey (middle panel of Table III.1). As seen in the lower panel of Table III.1, the resulting sample size for this report ranges from 414 youth for FUPTP to 715 for Teens in Control. The total sample size across the four sites totals 2,057 youth.
Evidence suggests that the program and control groups are well matched, as would be expected given an experimental design. Across a wide range of baseline measures, only a minimal number of differences between the program and control groups were statistically significant-no more than expected by random chance. For example, of over 40 measures based on baseline data (see Appendix Table A.1), no more than seven in each site show a statistically significant difference between the program group and control group.