Immunization Delivery and Policy as an Ongoing Model for Systems Improvement.

The authors studied the impact of a bidirectional exchange of pediatric immunization information between an electronic health record in a large urban ambulatory care network and a citywide immunization information system. They found that immunization up-to-date status increased in all age groups by 81.6% after implementation of the exchange. Importantly, the percent of overimmunized children decreased from 8.8% to 4.7% and was especially pronounced in adolescents (16.4% overimmunized preimplementation to 1.2% postimplementation). These findings have direct practical consequences, saving children from receiving unnecessary immunizations, preserving vaccine supplies, and allowing valuable clinical resources to be targeted to outreach children who are truly underimmunized.