Age-specific strategies for immunization reminders and recalls: a registry-based randomized trial

Am J Prev Med. 2014 Jul;47(1):1-8. doi: 10.1016/j.amepre.2014.02.009. Epub 2014 Apr 18.

Abstract

Background: Although previous studies have found reminder/recall to be effective in increasing immunization rates, little guidance exists regarding the specific ages at which it is optimal to send reminder/recall notices.

Purpose: To assess the relative effectiveness of centralized reminder/recall strategies targeting age-specific vaccination milestones among children in urban areas during June 2008-June 2009.

Methods: Three reminder/recall strategies used capabilities of the Michigan Care Improvement Registry (MCIR), a statewide immunization information system: a 7-month recall strategy, a 12-month reminder strategy, and a 19-month recall strategy. Eligible children were randomized to notification (intervention) or no notification groups (control). Primary study outcomes included MCIR-recorded immunization activity (administration of ≥1 new dose, entry of ≥1 historic dose, entry of immunization waiver) within 60 days following each notification cycle.

Results: A total of 10,175 children were included: 2,072 for the 7-month recall, 3,502 for the 12-month reminder, and 4,601 for the 19-month recall. Immunization activity was similar between notification versus no notification groups at both 7 and 12 months. Significantly more 19-month-old children in the recall group (26%) had immunization activity compared to their counterparts who did not receive a recall notification (19%).

Conclusions: Although recall notifications can positively affect immunization activity, the effect may vary by targeted age group. Many 7- and 12-month-olds had immunization activity following reminder/recall; however, levels of activity were similar irrespective of notification, suggesting that these groups were likely to receive medical care or immunization services without prompting.

Trial registration: ClinicalTrials.gov NCT01770496.

Publication types

  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Age Factors
  • Humans
  • Immunization / statistics & numerical data*
  • Immunization Programs / methods*
  • Infant
  • Michigan
  • Registries
  • Reminder Systems*
  • Time Factors
  • Urban Population
  • Vaccination / statistics & numerical data*

Associated data

  • ClinicalTrials.gov/NCT01770496