Importance: Reminder/recall notifications used by primary care practices increase the rates of childhood immunizations, but fewer than 20% of primary care practitioners nationally deliver such reminders. A reminder/recall notification conducted centrally by health departments in collaboration with primary care practices may reduce practice burden, reach children without a primary care practitioner, and decrease the cost of reminders/recalls.
Objective: To assess the effectiveness and cost-effectiveness of collaborative centralized (CC) vs practice-based (PB) reminder/recall approaches using the Colorado Immunization Information System (CIIS).
Design, setting, and participants: We performed a randomized pragmatic trial from September 7, 2012, through March 17, 2013, including 18,235 children aged 19 to 35 months in 15 Colorado counties.
Interventions: In CC counties, children who needed at least 1 immunization were sent as many as 4 reminders/recalls by mail or autodialed telephone calls by the CIIS. Primary care practices in these counties were given the option of endorsing the reminder/recall notification by adding the practice name to the message. In PB counties, primary care practices were invited to web-based reminder/recall training and offered financial support for sending notifications.
Main outcomes and measures: Documentation of any new immunization within 6 months constituted the primary outcome; achieving up-to-date (UTD) immunization status was secondary. We assessed the cost and cost-effectiveness of each approach and used a generalized linear mixed-effects model to assess the effect of the intervention on outcomes.
Results: In PB counties, 24 of 308 primary care practices (7.8%) attended reminder/recall training and 2 primary care practices (0.6%) endorsed reminder/recall notifications. Within CC counties, 129 of 229 practices (56.3%) endorsed the reminder/recall letter. Documentation rates for at least 1 immunization were 26.9% for CC vs 21.7% for PB counties (P < .001); 12.8% vs 9.3% of patients, respectively, achieved UTD status (P < .001). The effect of CC counties on children's UTD status was greater when the reminder/recall notification was endorsed by the primary care practice (19.2% vs 9.8%; P < .001). The total cost of the CC reminder/recall was $28 620 or $11.75 per child for any new immunization and $24.72 per child achieving UTD status; the total cost to the 2 practices that conducted PB reminders/recalls was $74.00 per child for any immunization and $124.45 per child achieving UTD status. The modeling resulted in an adjusted odds ratio of 1.31 (95% CI, 1.16-1.48) for any new immunization in CC vs PB counties.
Conclusions and relevance: A CC reminder/recall notification was more effective and more cost-effective than a PB system, although the effect size was modest. Endorsement by practices may further increase the effectiveness of CC reminder/recall.
Trial registration: clinicaltrials.gov Identifier: NCT01557621.