Immunization Data Exchange With Electronic Health Records.

OBJECTIVE To assess the impact of exchange of immunization information between an immunization information system (IIS) and an electronic health record on up-to-date rates, overimmunization, and immunization record completeness for low-income, urban children and adolescents. METHODS The New York City Department of Health maintains a population-based IIS, the Citywide Immunization Registry (CIR). Five community clinics in New York City implemented direct linkage of immunization data from the CIR to their local electronic health record. We compared immunization status and overimmunization in children and adolescents 19 to 35 month, 7 to 10 year, and 13 to 17 year-olds with provider visits in the 6-month period before data exchange implementation (2009; n = 6452) versus 6-months post-implementation (2010; n = 6124). We also assessed immunization record completeness with and without addition of CIR data for 8548 children and adolescents with visits in 2012-2013. RESULTS Up-to-date status increased from before to after implementation from 75.0% to 81.6% (absolute difference, 6.6%; 95% confidence interval [CI], 5.2% to 8.1%) and was significant for all age groups. The percentage overimmunized decreased from 8.8% to 4.7% (absolute difference, -4.1%; 95% CI, -7.8% to -0.3%) and was significant for adolescents (16.4% vs 1.2%; absolute difference, -15.2%; 95% CI, -26.7 to -3.6). Up-to-date status for those seen in 2012 to 2013 was higher when IIS data were added (74.6% vs 59.5%). CONCLUSIONS This study demonstrates that data exchange can improve child and adolescent immunization status. Development of the technology to support such exchange and continued focus on local, state, and federal policies to support such exchanges are needed.