Science Spotlight

Easing parents’ HPV vaccine hesitancy with a communication experiment

From the Shah Group, Division of Public Health Sciences

As of 2019, 54% of adolescents aged 13-17 years completed the completed the human papillomavirus (HPV) vaccine series. Although the percentage was below the Healthy People 2020 goal of 80%, the vaccine completion percentage may have dramatically decreased because of the COVID pandemic. Vaccine hesitancy has been identified as a top 10 threat to global health. Because of the current state of emergency, it’s possible that vaccine hesitancy has worsened. Previous studies have reported the importance of the communication approach to achieve higher completion of the HPV series and other vaccines. Dr. Shah, the first author of the paper from the Division of Public Health Sciences, explained, “Healthcare providers are incredibly influential when it comes to helping parents make decisions about getting their children vaccinated. However, there is a lot of misinformation and misunderstanding about this vaccine, so we wanted to find effective ways for providers to talk about HPV vaccine that is medically accurate, unambiguous to parents and their children, and saves time in clinical encounters so other health topics can be discussed.”

The Announcement Approach, recognized by the National Cancer Institute as an Evidence-Based Cancer Control Program, has increased HPV vaccine completion in primary care clinics. Three steps are suggested during the administration of the Announcement Approach: begin with informing parents that the child is due for the HPV vaccine and will receive it towards the end of their health visit (the Announcement step), answer all parents’ questions or concerns about vaccination (the Ease step), and encourage HPV vaccination (the Encouragement step). The Shah Group evaluated the second and third steps of the Announcement Approach and hypothesized that parents who completed the Ease step would report decreased HPV vaccine hesitancy, increased confidence, and discern that the physician recommendation was stronger compared to those who did not complete the Ease step. Dr. Shah stated, “. It is important to understand how these later components of the Approach impact parents vaccine perceptions, as it can point to what are the “active” or essential ingredients that can be refined for new, more focused and effective version of the communication strategy.” The paper is published in the American Journal of Preventive Medicine.

Participants in the study were US members of a national online probability panel of 60,000 adults maintained by Ipsos. The Announcement Approach utilized a 2x2 factorial design to introduce the parents to brief videos recommending the HPV vaccination. A sample of 1,196 parents viewed the video messages. First, the participants viewed the Announcement video. Next, the survey software randomly assigned the parents to receive the Ease video, the Encourage video, both videos, or neither of the videos. To develop the videos, the authors consulted with health communication scientists and vaccine prescribing physicians. The texts in the videos were refined to suit parents of all educational levels.  

Graphical Representation of Adolescent Vaccination
Adolescent Vaccination Image from Creative Commons website

Sixteen adolescent parents participated in cognitive survey testing and a total of 31 parents from the national panel participated in a pilot test of the survey to validate its functionality. The survey assessed the parents’ HPV vaccine hesitancy, HPV vaccine confidence, perceived vaccine recommendation strength, general attitudes toward vaccines, and trait reactance. The Shah Group utilized 2x2 between-subjects factorial ANOVA to evaluate the impact of the Ease and Encouragement videos, the Tukey-Kramer post-hoc test for analyzing interactions among several comparisons, and three-way ANOVA to examine potential moderators of the impact of vaccine hesitancy, vaccine confidence, and perceived recommendation strength.  Because the authors’ hypothesized that easing parents’ concerns and encouraging HPV vaccination could increase HPV vaccine confidence and decrease their hesitancy, structural equation modeling was used to evaluate whether vaccine confidence is an effect modification of Ease and Encouragement videos on vaccine hesitancy.

Parents exposed to Ease videos reported decreased HPV vaccine hesitancy compared to those not exposed to the Ease videos (P<.0001). Parents who watched the Ease videos reported higher confidence in the benefit of the HPV vaccine compared to those who didn’t watch the Ease videos (p=0.008). Encourage videos had no impact on vaccine hesitancy (p =0.19). Parents who watched the Encouragement videos reported similar confidence to those who didn’t watch the videos (p-0.87). The interaction between Ease and Encouragement was not statistically significant.  Parents with higher HPV vaccine confidence after watching videos reported lower hesitancy to get their child vaccinated. The Ease videos had significant indirect effect on hesitancy through confidence (β =-0.740, 95% CI= -0.774, -0.703).  The Encourage videos did not have a significant indirect effect on hesitancy through confidence.

The Path Group summarized that the Ease step is recommended in the Announcement approach to address the parents’ concerns about HPV. However, the Encouragement step should be included at the provider’s discretion when recommending the HPV vaccine to hesitant parents. Dr. Shah concluded, “To get feedback from a large, national sample of parents on the different steps of the Announcement Approach, using video messages made the most sense. Most previous studies tested messages using other media, like texts or infographics. While useful, reading a message is different than viewing a message being spoken by a person. As we wanted to approximate a clinical encounter as closely as possible, we decided to record our messages and have them delivered by a pediatrician. This adds to the ecological validity of our study, as parents viewed a message delivered by a pediatrician as they would if they were face-to-face with their child’s healthcare provider during a well visit or healthcare appointment.” International distribution of this training can benefit from the findings in this study and, at large, decrease the percentage of HPV cancers by increasing HPV vaccinations.

The researchers explained their future research direction, “The study we conducted helped identify the essential components of the communication strategy, and the team will continue testing the Approach in clinical settings to continue to refine and improve the communication steps so that it is easy and memorable for clinicians to use in vaccine discussions, saves them time, and ultimately helps improve HPV vaccine acceptance and uptake.”

This research was supported by a Centers for Disease Control and Prevention (CDC) grant.

Fred Hutch/UW Cancer Consortium member Parth D. Shah contributed to this work.

Shah PD, Calo WA, Gilkey MB, Margolis MA, Dailey SA, Todd KG, Brewer NT. Easing Human Papillomavirus Vaccine Hesitancy: A Communication Experiment With US Parents. American Journal of Preventive Medicine. 2021 May 8.https://doi.org/10.1016/j.amepre.2021.02.009