Walsh K, Zwi K, Woolfenden S, Shlonsky A.
Cochrane Database Syst Rev. 2015 Apr 16;4:CD004380. [Epub ahead of print]
BACKGROUND: Child sexual abuse is a significant global problem in both magnitude
and sequelae. The most widely used primary prevention strategy has been the
provision of school-based education programmes. Although programmes have been
taught in schools since the 1980s, their effectiveness requires ongoing scrutiny.
OBJECTIVES: To systematically assess evidence of the effectiveness of
school-based education programmes for the prevention of child sexual abuse.
Specifically, to assess whether: programmes are effective in improving students'
protective behaviours and knowledge about sexual abuse prevention; behaviours and
skills are retained over time; and participation results in disclosures of sexual
abuse, produces harms, or both.
SEARCH METHODS: In September 2014, we searched CENTRAL, Ovid MEDLINE, EMBASE
and 11 other databases. We also searched two trials registers and screened the
reference lists of previous reviews for additional trials.
SELECTION CRITERIA: We selected randomised controlled trials (RCTs),
cluster-RCTs, and quasi-RCTs of school-based education interventions for the
prevention of child sexual abuse compared with another intervention or no
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the
eligibility of trials for inclusion, extracted data, and assessed risk of bias.
We summarised data for six outcomes: protective behaviours; knowledge of sexual
abuse or sexual abuse prevention concepts; retention of protective behaviours
over time; retention of knowledge over time; harm; and disclosures of sexual
MAIN RESULTS: This is an update of a Cochrane Review that included 15 trials (up
to August 2006). We identified 10 additional trials for the period to September
2014. We excluded one trial from the original review. Therefore, this update
includes a total of 24 trials (5802 participants). We conducted several
meta-analyses. More than half of the trials in each meta-analysis contained unit
of analysis errors.1. Meta-analysis of two trials (n = 102) evaluating protective
behaviours favoured intervention (odds ratio (OR) 5.71, 95% confidence interval
(CI) 1.98 to 16.51), with borderline low to moderate heterogeneity (Chi² = 1.37,
df = 1, P value = 0.24, I² = 27%, Tau² = 0.16). The results did not change when
we made adjustments using intraclass correlation coefficients (ICCs) to correct
errors made in studies where data were analysed without accounting for the
clustering of students in classes or schools.2. Meta-analysis of 18 trials (n =
4657) evaluating questionnaire-based knowledge favoured intervention
(standardised mean difference (SMD) 0.61, 95% CI 0.45 to 0.78), but there was
substantial heterogeneity (Chi² = 104.76, df = 17, P value < 0.00001, I² = 84%,
Tau² = 0.10). The results did not change when adjusted for clustering (ICC: 0.1
SMD 0.66, 95% CI 0.51 to 0.81; ICC: 0.2 SMD 0.63, 95% CI 0.50 to 0.77).3.
Meta-analysis of 11 trials (n =1688) evaluating vignette-based knowledge favoured
intervention (SMD 0.45, 95% CI 0.24 to 0.65), but there was substantial
heterogeneity (Chi² = 34.25, df = 10, P value < 0.0002, I² = 71%, Tau² = 0.08).
The results did not change when adjusted for clustering (ICC: 0.1 SMD 0.53, 95%
CI 0.32 to 0.74; ICC: 0.2 SMD 0.60, 95% CI 0.31 to 0.89).4. We included four
trials in the meta-analysis for retention of knowledge over time. The effect of
intervention seemed to persist beyond the immediate assessment (SMD 0.78, 95% CI
0.38 to 1.17; I² = 84%, Tau² = 0.13, P value = 0.0003; n = 956) to six months
(SMD 0.69, 95% CI 0.51 to 0.87; I² = 25%; Tau² = 0.01, P value = 0.26; n = 929).
The results did not change when adjustments were made using ICCs.5. We included
three studies in the meta-analysis for adverse effects (harm) manifesting as
child anxiety or fear. The results showed no increase or decrease in anxiety or
fear in intervention participants (SMD -0.08, 95% CI -0.22 to 0.07; n = 795) and
there was no heterogeneity (I² = 0%, P value = 0.79; n=795). The results did not
change when adjustments were made using ICCs.6. We included three studies (n =
1788) in the meta-analysis for disclosure of previous or current sexual abuse.
The results favoured intervention (OR 3.56, 95% CI 1.13 to 11.24), with no
heterogeneity (I² = 0%, P value = 0.84). However, adjusting for the effect of
clustering had the effect of widening the confidence intervals around the OR
(ICC: 0.1 OR 3.04, 95% CI 0.75 to 12.33; ICC: 0.2 OR 2.95, 95% CI 0.69 to
12.61).Insufficient information was provided in the included studies to conduct
planned subgroup analyses and there were insufficient studies to conduct
meaningful analyses.The quality of evidence for all outcomes included in the
meta-analyses was moderate owing to unclear risk of selection bias across most
studies, high or unclear risk of detection bias across over half of included
studies, and high or unclear risk of attrition bias across most studies. The
results should be interpreted cautiously.
AUTHORS' CONCLUSIONS: The studies included in this review show evidence of
improvements in protective behaviours and knowledge among children exposed to
school-based programmes, regardless of the type of programme. The results might
have differed had the true ICCs or cluster-adjusted results been available. There
is evidence that children's knowledge does not deteriorate over time, although
this requires further research with longer-term follow-up. Programme
participation does not generate increased or decreased child anxiety or fear,
however there is a need for ongoing monitoring of both positive and negative
short- and long-term effects. The results show that programme participation may
increase the odds of disclosure, however there is a need for more programme
evaluations to routinely collect such data. Further investigation of the
moderators of programme effects is required along with longitudinal or data
linkage studies that can assess actual prevention of child sexual abuse.