Sex Education and Other Programs that Work to Prevent Teen Pregnancy, HIV and Sexually Transmitted Infections

Full Study Report [HTML] [PDF]
Executive Summary [HTML] [PDF]

Although Advocates for Youth strove for consistency in terminology, it may still vary. For example, some evaluations provide information about African American participants, others about black participants. These two terms are not necessarily interchangeable since they may denote different populations. Therefore, Advocates for Youth used the evaluators' language as to race/ethnicity and risk (i.e., low risk, high risk, or moderate risk).

Participant Groups

• Control or comparison group = young people with similar socioeconomic, ethnic, and demographic characteristics as the intervention group, yet who did not receive the program being evaluated, and whose answers at pretest and post-intervention follow-up provided evaluators with data for comparison with intervention participants, in order to determine the effectiveness of the program. The nonparticipant group is called a control group when youth are selected randomly and a comparison group when they are not.
• Treatment or intervention group = the young people who received the program being evaluated.

Evaluation Design

• Experimental design = an evaluation design that involves gathering a set of individuals equally eligible and willing to participate in a program and randomly dividing them into two groups: those who receive the intervention (treatment group) and those from whom the intervention is withheld (control group). By randomly allocating the intervention among eligible beneficiaries, the assignment process creates comparable treatment and control groups that are statistically equivalent with one another, given appropriate sample sizes.
• Non-experimental design = an evaluation design for use when it is not possible to select a control group, identify a suitable comparison group through matching methods, or use methods, or use reflexive comparisons.[*]
• Quasi-experimental design = an evaluation design that constructs a comparison group using matching or reflexive comparisons. Matching involves identifying non-program participants comparable in essential characteristics to participants; both groups are matched on the basis of either a few observed characteristics or a number of characteristics that are known, or believed, to influence program outcomes. Reflexive comparison involves program participants, compared to themselves before and after the intervention and who function as both treatment and control group.[*]

Related Terms

• Replication = the same program, evaluated in another place with different young people.
• Fidelity = careful replication of a program to include all its elements as included in the original evaluation. Where programs were altered, lack of fidelity is noted in this document.
• For Use With = used here to denote the populations of young people with whom evaluation has shown a particular program to be most effective as well as the population for whom it was designed.
• Significant = statistically significant, or meaningful difference, as determined by evaluation.

* Definition from http://www.worldbank.org/poverty/impact/methods/overview.htm