Introduction: Current adult vaccination rates fall well below the Healthy People 2020 goals established by the Centers for Disease Control and Prevention for pneumococcal, influenza, pertussis, and herpes zoster vaccines. The objective of this study was to improve immunization rates in primary care through an enhanced, multi-component "audit & feedback" (A&F) intervention.
Methods:The intervention took place over a one-year period (September 2016-August 2017) and involved 24 primary care clinics within one health system in North Carolina. It consisted of pre-specified targets and an online A&F platform, combined with multidisciplinary educational resources and non-physician clinic champions. Six control clinics in the same health system were also identified. Clinic and provider performance for immunization for pneumococcal, influenza, pertussis, and herpes zoster vaccines were tabulated on a monthly basis. Rates were benchmarked against a clinic-defined target, other participating clinics' immunization rates, and national targets. Results were displayed on an electronic dashboard within the online platform, and printable reports were given to each clinic to post in work areas and discuss at practice meetings on a monthly basis. Educational efforts primarily focused on non-physician clinical personnel (nurses, medical assistants) and consisted of online learning modules and 5-minute videos. Frontline nurses or medical assistants served as site champions to receive and distribute monthly immunization reports and attend quarterly project calls to discuss barriers and solutions with champions from the other clinics. Comparisons between intervention and control clinic groups were made using the t-test or Wilcoxon rank-sum test for continuous variables depending on normality, or Pearson's chi square test for categorical variables. To assess the effectiveness of the intervention, the likelihood of immunization during the intervention period was compared between intervention and control clinics using logistic regression models. The generalized estimating equations method was used to account for clustering of outcomes within clinics. Analyses included adjusting for baseline vaccination rates and differences in case mix between intervention and control clinics.Results: A total of 209,533 and 64,133 patients were seen in the intervention and control clinics, respectively. Intervention patients were younger (mean age 51 years vs. control 53 years, p < 0.0001) and had higher proportions of patients who were female (60% vs. control 55%, p < 0.0001), and privately insured (65% vs. control 58%, p < 0.0001), but a lower proportion of Caucasian patients (65% vs. control 72%, p < 0.0001). All vaccine types showed increases in immunization rates during the intervention period in both intervention and control practices. After accounting for covariates, patients seen in the intervention clinics were more likely to receive an influenza vaccine (adjusted OR 1.27, 95% CI 1.02-1.58, p = 0.03) and complete the pneumococcal vaccine series (...