Effect of the framing of HPV vaccination on parents' willingness to accept an HPV vaccine.

In China, HPV vaccines are not mandatory and have low uptake. In light of the U.S.'s experience in rolling out the vaccine with an initial focus primarily on HPV as a sexually transmitted infection but transitioning later to cancer messaging, we used a multifactorial experiment to create several different messages about the HPV vaccine across age, communicability, and cancer domains. In this study, we assess the effect of the different messages on willingness to accept an HPV vaccine, and characterize how parental sociodemographics and the age/gender of a child also impact willingness to obtain an HPV vaccine. In total, 1,021 parents of children aged<18 years old in Shanghai, China were randomized to receive a message about cancer (HPV causes cervical cancers vs cancers in general), infectiousness (HPV is sexually transmitted, or is an infectious disease in general, or not mentioned), and recommended age of vaccination (before middle school, before college/work, or not mentioned). Parents were asked if they would vaccinate a hypothetical son or daughter of different ages 6, 12, or 18 years old). In a multivariable logistic regression model adjusting for parental sociodemographic characteristics, parents were more likely to want to vaccinate a daughter vs a son, and an older vs younger child. Messaging had some effect in certain circumstances: parents were more likely to accept a vaccine for a 6-year-old son if given information that it protected against cancers in general. Providing information about a sexually transmitted infection led to higher willingness to vaccinate a son 6 years old and a daughter 6 or 12 years old. This study showed messaging had some limited impact on willingness to vaccinate against HPV, but more research is needed on how to increase uptake of the HPV vaccine when it is not publicly funded.