Text message reminders for timely routine MMR vaccination: A randomized controlled trial

Objective: Measles-mumps-rubella (MMR) vaccination is important for preventing disease outbreaks, yet pockets of under-vaccination persist. Text message reminders have been employed successfully for other pediatric vaccines, but studies examining their use for MMR vaccination are limited. This study assessed the impact of text message reminders on timely MMR vaccination.

Study design: Parents (n=2054) of 9.5-10.5-month-old children from four urban academically-affiliated pediatric clinics were randomized to scheduling plus appointment text message reminders, appointment text message reminder-only, or usual care. The former included up to three text reminders to schedule the one-year preventive care visit. Both text messaging arms included a text reminder sent 2 days before that visit. Outcomes included appointment scheduling, appointment attendance, and MMR vaccination by age 13 months, the standard of care at study sites.

Results: Children of parents in the scheduling plus appointment text message reminders arm were more likely to have a scheduled one-year visit than those in the other arms (71.9% vs. 67.4%, relative risk ratio (RRR) 1.07 [95% CI 1.005-1.13]), particularly if no appointment was scheduled before randomization (i.e., no baseline appointment) (62.1% vs. 54.7%, RRR 1.14 [95% CI 1.04-1.24]). One-year visit attendance and timely MMR vaccination were similar between arms. However, among children without a baseline appointment, those with parents in the scheduling plus appointment text message reminders arm were more likely to undergo timely MMR vaccination (61.1% vs. 55.1%, RRR 1.11 [95% CI 1.01-1.21]).

Conclusion: Text message reminders improved timely MMR vaccination of high-risk children without a baseline one-year visit.