Review: patient reminder or recall systems improve immunization rates.

D a t a e x t r a c t i o n Data were extracted on patient age (newborn to adult); setting (academic, public health, or private); intervention delivery (letter, postcard, telephone, autodialer, or in person), specificity (generic or personal reminders), and number (1-time or multiple reminders); and vaccination schedule. Study quality was assessed (allocation concealment, blinding, follow-up, reliable primary outcome measure, and protection against contamination). Outcomes were immunization rates or the proportion of the target population that was up to date on recommended immunizations.