Importance: Caregiver-targeted interventions to improve the use of child restraint systems (CRS) in motor vehicles are common and heterogeneous in their implementation. The effectiveness of these interventions is unknown.
Objectives: To quantify the effects of caregiver-targeted interventions using meta-analytic methods, assess the quality of published studies, and assess for publication bias.
Data sources: PubMed and PsychINFO (January 1, 2004, to April 1, 2019) were searched for English-language studies using a list of search terms. The search and screening process was completed between May 25, 2018, and April 1, 2019.
Study selection: Studies met inclusion criteria if they included a caregiver-targeted intervention that focused on increasing CRS use for children (age, ≤9 years) and report the use of CRS before and after the intervention.
Data extraction and syntheses: Cochrane and PRISMA guidelines were used for the meta-analysis and risk-of-bias review. Information was extracted on intervention type, setting, implementation, and attributes of the study independently between 2 coders. Data were pooled from independent samples, with 1 outcome measure from each intervention implementation or study.
Main outcomes and measures: This study was an exploratory random-effects meta-analysis. Unadjusted odds ratios were calculated using the sample size and the observed number of children in incorrect or correct restraints in motor vehicles before and after the intervention to determine the odds of incorrect CRS use after completing an intervention. Setting, measurement method, randomization, use of vouchers, and types of restraint were tested as moderators. A funnel plot was used to assess for publication bias.
Results: Of 1240 potential articles, 51 were deemed eligible for screening and 10 (8238 participants total) were included in the meta-analysis. Caregiver-targeted interventions were associated with a reduction in the number of children not riding in a CRS (odds ratio, 0.51; 95% CI, 0.36-0.71; P < .001). Variance in the averaged effect size was driven by self-report methods (when removed from analyses, I2 = 61.8%; R2 change = 26.3; P = .02) and hospital settings (when removed from analyses, I2 = 70.7%; R2 change = 17.4; P = .002). Risk of bias was high in most studies; however, there was low evidence for publication bias.
Conclusions and relevance: In this meta-analysis, caregiver-targeted interventions were associated with a reduction in the number of children not riding in a CRS in motor vehicles; however, the methodological rigor of intervention studies should be enhanced.