Study Details


Carter SL, Beadnell B, Vanslyke J. Evaluation of the Web of Life teen pregnancy prevention program: Findings from an innovative positive youth development approach for American Indian youth. National Indian Youth Leadership Project. 2015.

Program Name

Web of Life

Show Evidence of Effectiveness
Study Rating and Explanation

Quasi-experimental study that met all criteria for a moderate rating; findings show no positive, statistically significant impact on a relevant behavioral outcome measure for either the full sample or key subgroups

Program Information

Program Type
Positive youth development
Program Length
More than 20 sessions

Evaluation Setting

Evaluation Setting
Multiple settings

Study Sample

Average Age Group
13 or younger
Majority Racial/Ethnic Group
American Indian or Alaska Native
Youth of any gender

Research Design

Assignment Method
Quasi-Experimental Design
Sample Size


Number of Follow-Ups


Length of Last Follow-Up


Year of Last Data Collection
Reviewed Studies
Moderate-Quality Quasi-Experiment
Protocol Version
Version 5.0
Effect Sizes
{"0": {"ProgramName":"Web of Life","StudyID":"PPRER016014","ManuscriptID":"PPRER016014","Rating":"Moderate","OutcomeName":"Ever had sexual intercourse","OutcomeDomain":"Sexual Activity","OutcomeDichotomous":"Yes","SampleType":"Full sample","FUTimingMonths":"12","FUReference":"Baseline","MeanTreat":"0.02","MeanComp":"0.02","TpperES":"0.000","StatSigRepEffect":"No","RepEffectFavorable":"Not significant","RepEffectMeet":"No"},"1": {"ProgramName":"Web of Life","StudyID":"PPRER016014","ManuscriptID":"PPRER016014","Rating":"Moderate","OutcomeName":"Ever had sexual intercourse","OutcomeDomain":"Sexual Activity","OutcomeDichotomous":"Yes","SampleType":"Subgroup--other","FUTimingMonths":"18","FUReference":"Baseline","MeanTreat":"0.04","MeanComp":"0.01","TpperES":"0.859","StatSigRepEffect":"No","RepEffectFavorable":"Not significant","RepEffectMeet":"No"}}

NA = Not available. This means the authors did not report the information in the manuscripts associated with the studies we reviewed.

a This information was not available whenever authors did not report information for the treatment and comparison groups separately on outcome means, standard deviations, and/or sample sizes.

b Authors reported that the program effect (impact) estimate is statistically significant with a p-value of less than 0.05 based on a two-tailed test.

c For some outcomes, having less of that outcome is favorable. In those cases, an effect with a negative sign is favorable to the treatment group (that is, the treatment group had a more favorable outcome than the comparison group, on average).

d An effect shows credibly estimated, statistically significant evidence whenever it has a p-value of less than 0.05 based on a two-tailed test, includes the appropriate adjustment for clustering (if applicable), and it is not based on an endogenous subgroup.