Can mHealth Interventions Contribute to Increased HPV Vaccination Uptake? A Systematic Review

"[T]he majority of the included studies targeted minority groups such as Latinos or socio-economically disadvantaged groups. This could indicate that the study findings could potentially be replicated also in ethnically and socioeconomically diverse groups within and outside the United States."

Human papillomavirus (HPV) vaccination uptake remains suboptimal across the globe, including in North American and European countries where vaccine availability is not a significant barrier. Multiple health promotion interventions are used to address the problem of low vaccine uptake, including digital technologies. The objective of this review was to synthesise existing evidence on mobile health (mHealth) interventions geared at improving HPV-related knowledge, HPV vaccination intent, and HPV vaccination uptake.

Between November and December 2019, the researchers performed systematic searches, identifying 805 articles. Nineteen articles met inclusion criteria, 11 of which were randomised control trials; all but one were conducted in the United States (US). mHealth interventions ranged from text messages and phone calls to interactive voice recordings and software on tablets. (Table 1 in the paper provides an overview of the included studies.) Most of the interventions were based on the assumption that reminding parents, young adults, or adolescents of the intervention schedule would increase vaccine uptake. (An overview of the intervention designs is found in Table 2.)

Four interventions attempted to improve HPV knowledge and vaccination intent. Two of them used tailored messages: Lee et al. (2016) used culturally tailored SMS (short messaging service) based on principles of community participatory research and the Fogg Behavior Model. The messages were tested with focus groups and featured testimonies from peers about cervical cancer and the HPV vaccine, while providing information about locations for vaccination and testing. Dempsey et al. (2019) used tailored health messaging in clinic waiting rooms to reach Latino parents of adolescents or young adults. All 4 of the interventions in this category reported positive findings; however, only 2 reported statistically significant improvements between intervention and control groups.

Of the 10 studies that used text message reminders, 9 reported an increased receipt of vaccination. When assessing telephone reminders in comparison to other reminder systems, vaccination and completion rates did not differ. Overall, 14 interventions reported an increase in HPV vaccination uptake and vaccination series completion among the intervention groups, including when mHealth interventions were compared to control groups or non-mHealth interventions.

Some factors noted in successful interventions included: frequency of messages; combinations of multiple interventions, including in-person education session, written educational materials, and texts alongside call or emails; tailored messages; and participants' intent to vaccinate at baseline.

Notably, most of the studies were designed to reach parents. "Considering the growing technological awareness and engagement among adolescents and young adults, not targeting adolescents and young adults in mHealth interventions geared at improving HPV knowledge, intent and vaccination might be a missed opportunity. This, of course, must include the consideration that while in some contexts adolescents may be independent decision-makers about vaccinations, this is not the case in most countries."

In short, despite the variation in intervention designs, all but 5 studies reported increases in knowledge, intent to vaccinate, or vaccination uptake. However, these findings cannot be linked to any specific format of mHealth intervention. Overall, the majority of the included studies did not elucidate their theoretical understanding of health education, health communication, mHealth intervention development, or adoption. In addition to the need to fully engage with theory, further study is warranted to support existing evidence suggesting that tailoring health messages to populations or individuals who are less well informed or who hold negative attitudes towards HPV vaccination could lead to improved health outcomes.

Reflecting on possibilities going forward, the researchers note that adoption of mHealth is known to be influenced by methods used in the development process of the intervention, including creating ownership among the intended population. One way to do this is through use of co-creation methods and usability assessments in the development and pilot testing phases of mHealth. Paying attention to known sub-population needs and trends could also be of importance in addressing issues related to the digital divide. This lens is pertinent to ensuring that a reliance on technological interventions does not worsen disparities in health access.

In conclusion: "mHealth interventions potentially show promise as tools in improving short-term vaccination knowledge, intent, and uptake of HPV vaccination. There is however a need to refine components which can promote mHealth interventions' success as well as for the evaluation of such interventions in different contexts and over time."