Collaborative Centralized Reminder/Recall Notification to Increase Immunization Rates Among Young Children: A Comparative Effectiveness Trial.

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 c