Cost-effectiveness of SMS appointment reminders in increasing vaccination uptake in Lagos,Nigeria: A multi-centered randomized controlled trial

ObjectiveIt is expected that mHealth largely contribute to increasing the coverages of key maternal and child health services. This study aims to estimate the cost-effectiveness of the SMS text reminders in clients’ return visits to the health facilities for child vaccinations (incl. vitamin A supplementations), antenatal care (ANC) and family planning (FP), in urban communities of Lagos, Nigeria.MethodsA multi-centered randomized control trial was conducted at 33 primary health centers (PHCs) in Lagos, Nigeria. All the clients having visited any of the 33 PHCs for child vaccinations, ANC and FP were randomly assigned either to intervention group or to control group.The participants in the intervention group were sent an SMS text reminder two days before their appointments. Those not having showed up on the appointment dates received an additional SMS text reminder seven days after original appointment dates as defaulter tracing. The primary outcome was whether a client made return visit to PHCs for the upcoming appointments.ResultsOf 12,779 appointments for 9,368 clients during the period of 1st April to 30th June 2019, 12,175 were included in the analysis. The return rate for child vaccinations in the intervention group was significantly higher (p < 0.001) by 4.8% − 6.0% than that in the control group, consistently across all the five different timings (on time as scheduled, and by 7 days, 14 days, 30 days, and 3 months after appointment dates). No significant difference between the two groups was detected in the increase in return rates for ANC and FP services. The incremental recurrent cost was estimated at 7.90 US Dollars per return case.ConclusionSMS text reminders led to a significant increase in the number of return visits for child vaccinations, Lagos, Nigeria, while no significant increase in return visits was confirmed for ANC and FP appointments.