Improving Vaccination for Young Children (IVY): A Stepped-Wedge Cluster Randomized Trial

High childhood vaccination rates are critical for public health. We hypothesized that implementation of a vaccine education and quality improvement (QI) program, Improving Vaccinations for Young Children (IVY), would improve childhood vaccine rates.

Eight pediatric practices (3 academic-based, 5 community-based) were randomized to implement IVY within a stepped-wedge cluster randomized trial (SWCRT) in middle Tennessee. Two educational modules on vaccines were developed using best practices in instructional design. Modules were provided electronically and were tailored to providers or office staff. Practices completed in-person QI coaching sessions and selected at least 2 vaccination-related QI changes. Data were collected monthly. The primary analysis examined intervention effect on the primary outcome of Combination 10 vaccination status for children who turned 2 in the previous month. Combination 10 status without influenza vaccine was a secondary outcome, and exploratory analyses assessed intervention effects after adjusting for time and practice type.

Data from 4041 patients (1788 control; 2253 intervention) were collected. The intervention effect was not significant on the primary outcome (OR = 1.01; 95% CI [0.76, 1.34]; P > .9), however there were positive intervention effects in secondary and exploratory models analyzing Combination10 rates without flu, including models adjusting for variation over time (0.20; 95% CI [0.04,0.35]; P = .01) and practice type (higher vaccination rate in academic practices, 0.23; 95% CI [0.03,0.42]; P = .03).

Combination 10 rates were not significantly improved with IVY, yet evidence of beneficial effect on rates without flu vaccine was found. Future studies could evaluate effects over a longer time period and within a larger practice sample.