Peer-reviewed article
Short message service (SMS) reminders for childhood immunisation in low-income and middle-income countries: a systematic review and meta-analysis
Paul Eze, Lucky Osaheni Lawani, Yubraj Acharya ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This systematic review examined whether SMS text message reminders help improve childhood vaccination coverage in low- and middle-income countries. The researchers analysed 18 studies involving over 32,000 infants across 11 countries. SMS reminders significantly increased both the rate of children receiving vaccines and the timeliness of vaccination, with greater effectiveness in lower-income countries and when more than two reminders were sent.
Key points
- SMS reminders increased childhood immunisation coverage by 16% (risk ratio 1.16)
- SMS reminders increased timely receipt of vaccines by 21% (risk ratio 1.21)
- More effective in low-income and lower middle-income countries than upper middle-income countries
- Sending more than two SMS reminders was significantly more effective than sending one or two reminders
- Analysis included 13 randomised controlled trials and 5 non-randomised studies from 11 low- and middle-income countries
Limitations
The review found significant heterogeneity across studies (I²>87%), meaning results varied substantially between studies, which limits confidence in generalising findings. The document does not provide detailed information about the context, implementation costs, or sustainability of SMS reminder programmes.
Abstract
Introduction Childhood vaccine delivery services in the low- and middle-income countries (LMIC) are struggling to reach every child with lifesaving vaccines. Short message service (SMS) reminders have demonstrated positive impact on a number of attrition-prone healthcare delivery services. We aimed to evaluate the effectiveness of SMS reminders in improving immunisation coverage and timeliness in LMICs. Methods PubMed, Embase, Scopus, Cochrane CENTRAL, CINAHL, CNKI, PsycINFO and Web of Science including grey literatures and Google Scholar were systematically searched for randomised controlled trials (RCTs) and non-RCTs that evaluated the effect of SMS reminders on childhood immunisation and timeliness in LMICs. Risk of bias was assessed using the Cochrane Risk of Bias 2.0 assessment tool for RCTs and Cochrane Risk of Bias in Non-randomised Studies of Interventions tool for non-RCTs. Meta-analysis was conducted using random-effects models to generate pooled estimates of risk ratio (RR). Results 18 studies, 13 RCTs and 5 non-RCTs involving 32 712 infants (17 135 in intervention groups and 15 577 in control groups) from 11 LMICs met inclusion criteria. Pooled estimates showed that SMS reminders significantly improved childhood immunisation coverage (RR=1.16; 95% CI: 1.10 to 1.21; I2=90.4%). Meta-analysis of 12 included studies involving 25 257 infants showed that SMS reminders significantly improved timely receipt of childhood vaccines (RR=1.21; 95% CI: 1.12 to 1.30; I2=87.3%). Subgroup analysis showed that SMS reminders are significantly more effective in raising childhood immunisation coverage in lower middle-income and low-income countries than in upper middle-income countries (p<0.001) and sending more than two SMS reminders significantly improves timely receipt of childhood vaccines than one or two SMS reminders (p=0.040). Conclusion Current evidence from LMICs, although with significant heterogeneity, suggests that SMS reminders can contribute to achieving high and timely childhood immunisation coverage. PROSPERO registration number CRD42021225843.
Findings the Hub has extracted
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Problem