Strategies That Improved Childhood Routine Immunization Coverage

Key Takeaways

• Across 28 identified strategies, consistent gains were reported for cash transfers, home-based identification and outreach, and informational vaccination sessions.
• Cash transfers showed small gains, home-based outreach showed small-to-moderate gains, and informational sessions were associated with improved outcomes such as DTP-3.
• Most strategies were associated with incremental gains, with effects varying by context, delivery model, and vaccination stage.

Only a limited subset of approaches showed consistent positive effects on routine childhood immunization coverage in a global systematic review and meta-analyses published in Discover Public Health. The review drew on 35 studies that evaluated 28 distinct strategies. Investigators found the clearest benefits in a small group of interventions rather than across the broader strategy landscape. Gains were concentrated in a few approaches and varied across settings.

Across diverse settings, this global systematic review and meta-analyses examined strategies to improve childhood routine immunization coverage. In the review, searches covered MEDLINE, EMBASE, PsycINFO, and CINAHL, with additional citation searching. Researchers screened 3,251 citations, included 35 studies, and identified 28 distinct strategies. Eligible designs included randomized controlled trials, cluster randomized trials, and controlled before-after studies.

The clearest quantitative findings centered on three strategy groups. Conditional and unconditional cash transfers were associated with improved full vaccination coverage, with a pooled RR of 1.11, a 95% CI of 1.07 to 1.15, no observed heterogeneity, and two studies. Home-based identification and outreach showed a median RR of 1.23 with an interquartile range of 1.09 to 1.37 across two randomized studies. Informational vaccination sessions delivered in facilities or homes were associated with a pooled RR of 1.33, with a 95% CI of 1.03 to 1.62 in two studies, and improvement was noted for outcomes such as DTP-3.

The broader synthesis indicated that most strategies produced incremental gains rather than large shifts in coverage. Only a limited subset was supported by moderate-certainty evidence with low or some risk of bias. Childhood vaccination remained central to disease prevention, and an estimated 14.3 million children younger than five remained unvaccinated in 2024. The authors linked progress toward Immunization Agenda 2030 to reliable, system-compatible strategies tailored to local health systems, while noting that benefits differed by context, delivery model, and vaccination stage.