Effect of automated immunization registry-based telephonic interventions on adult vaccination rates in community pharmacies: A randomized controlled trial

Abstract

BACKGROUND: Pharmacies have a unique opportunity to address suboptimal adult vaccination rates, but few solutions have proven effective. Such strategies are challenged by the lack of access that many pharmacies have to a patient’s complete immunization history; consequently, they are unable to identify which of their patients actually require vaccination. A pharmacy-based strategy that leverages such information could enhance efforts to increase rates of guideline-based vaccination. OBJECTIVE: To determine the effect on vaccination rates of an automated telephonic intervention for adults in need of either pneumococcal vaccination or herpes zoster vaccination, or both. METHODS: Over a 1-year period, patients with identified vaccine gaps at 246 pharmacies of 3 pharmacy chains were randomly assigned to receive either usual care or an automated telephonic prompt for pneumococcal and/or herpes zoster vaccines based on patient records contained in state immunization registries and pharmacy data. The primary outcome was the proportion with administration of at least one of the vaccines offered between March 2016 and January 2017 based on intention-to-treat principles. Subgroup analyses included vaccination rates by age and sex. An as-treated analysis was also performed. RESULTS: 21,971 patients were included in the study, 57% of whom were female, with a mean age of 63 years. Vaccine administration proportions were 0.0214 (236/11,009) in the intervention group, and 0.0205 (225/10,962) in the control group (OR=1.05, 95% CI=0.87-1.26). Results did not differ in subgroup analyses based on patient age, sex, or individual pharmacy chain. Among intervention patients, 3,666 (0.333) completed the call by listening to the entire prompt. In an as-treated analysis comparing individuals who completed calls versus control, the intervention increased the odds of vaccination by 26% (OR=1.26, 95% CI=1.00-1.61). CONCLUSIONS: The automated prompt did not significantly increase vaccination rates. Potential barriers included intervention technical flaws, low rates of connecting with patients, insufficient follow-up by the pharmacy, and patients placing a relatively low priority on being vaccinated.