Provider Communication and Mothers' Willingness to Vaccinate Against Human Papillomavirus and Influenza: A Randomized Health Messaging Trial

To understand the effect of a health messaging intervention focused on provider communication about vaccination on mothers' willingness to vaccinate children against human papillomavirus (HPV) and seasonal influenza. A total of 2476 mothers of 9- to 13-year-olds in the United States completed a Web-based survey in August 2014. Mothers were randomized to 1 of 2 groups targeting HPV or influenza vaccine. Mothers whose child had not received the target vaccine (ie, zero doses of HPV vaccine/no prior-year administration of influenza vaccine) were randomized to the intervention. The study used a 3 × 2 between-subjects design; illustrated vignettes depicted 1 of 3 levels of provider recommendation strength (brief mention of vaccination, strong recommendation of vaccination, or personal disclosure of vaccination of own children), and presence or absence of information comparing safety of vaccination to the safety of a common daily activity. Outcome was mothers' willingness to have their child receive the target vaccine. Perceived benefits of vaccination were assessed before viewing the intervention and were included as a covariate in analyses, along with child gender. For HPV vaccine, there was a main effect of safety information (F(1,684) = 7.99, P = .005) and perceived benefits of vaccination (F(1,684) = 221.64, P