A Systematic Review of Behaviour Change Techniques within Interventions to Increase Vaccine Uptake among Ethnic Minority Populations

"The most common approach used is related to education and providing vaccine information to targeted populations, and this is most effective when provided in a visual format, delivered through credible sources which include healthcare professionals and respected community representatives, repeated exposure and providing follow-up opportunities for dialogue in a timely manner."

Changing behaviour is complex, and, therefore, a systematic approach is required to understand factors influencing vaccine uptake, such as knowledge, beliefs, attitudes, and behaviours of the intended population group. Vaccine hesitancy can be reduced, and uptake increased, when interventions target emotional, cognitive, and social determinants that can either hinder or facilitate this behaviour through culturally appropriate information and messaging, policy, and vaccine delivery. Some racial and ethnic minority communities have lower vaccine uptake, as was evident during the COVID-19 pandemic. This systematic review synthesises and evaluates behaviour change techniques (BCTs) in interventions to increase vaccination uptake in ethnic minority populations.

Interventions based on principles drawn from evidence and theories of behaviour and behaviour change have shown to be more effective. The Behaviour Change Wheel (BCW) and Behaviour Change Technique Taxonomy v1 (BCTTv1) are examples of tools for identifying and describing specific behavioural components. The BCW is a synthesis of 19 frameworks of behaviour change that can be used to characterise intervention components that contribute to behaviour change; within the BCW is the inner hub (capability, opportunity, and motivation, i.e., the COM-B model), which outlines sources of behaviour that could be the target for interventions. While the BCTTv1 is a 93-item taxonomy of BCTs, the two frameworks are complementary.

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the researchers searched five databases and grey literature sources. Searches had no date restriction; the search was conducted on March 24 2021 and updated on June 27 2022. From 7,637 records identified, 23 peer-reviewed studies were included in the review. Interventions were categorised using the BCW and BCTTv1. The vaccines targeted a wide range of illnesses, including influenza, pneumococcal disease, hepatitis, polio, pertussis, diphtheria and tetanus, and measles-mumps-rubella. The interventions were conducted between 2001 and 2021, ranging from two months to five years, primarily in health centres/clinics and community settings.

Twenty-six BCTs, six BCW intervention functions, and seven policy categories were identified to promote vaccine delivery and uptake in racial and ethnic minority groups. The most common BCTs used in at least six studies were: information about health consequences (to increase risk awareness and vaccine knowledge); information about antecedents (to advise patients about vaccination impacts); credible source (to provide guidelines and health workers' collaboration with community organisations); prompts/cues (to provide reminders and motivation); instruction on how to perform the behaviour (to present guidance on how to get vaccinated); restructuring of the physical environment (to provide ease of access to vaccine service); and framing/reframing (to present information in formats that can motivate change).

The main intervention functions used were education, persuasion, and enablement. Interventions conducted in community settings (n = 8 studies) primarily used an educational approach including coaching, case management, and media-led information and education outreach campaigns. The coaching intervention delivered two approaches: peer coaching with nurse case management (PC-NCM) and peer coaching alone, and compared these with usual care (which included minimal PC and nurse involvement). The case management intervention also provided health passports to parents, which only contained information on the recommended visits for well-child care and the childhood immunisation schedule. Some education interventions used community members to deliver the intervention, which included training peer health educators and using religious leaders to enhance recruitment and uptake in vaccination programmes. Three studies reported providing culturally specific information and interpretation in the local languages of the ethnic minority groups.

Outcomes of interest mainly focused on vaccine uptake and coverage amongst ethnic minority patients/participants (n = 19 studies). All interventions targeted ethnic minority populations' behaviour and were designed to access vaccine knowledge and perception, intention to vaccinate after the intervention, adoption of healthy behaviours, and cost-effectiveness. Overall, the effects of the different intervention functions and associated BCTs varied. All but one of the studies reported positive changes from the implemented interventions.

In general, effective interventions had multiple components and were tailored to specific populations. No strong evidence was observed to recommend specific interventions, but the most effective were those with a community-based component, such as offering community clinics and free vaccination, raising awareness, and involving community organisations. For example, Findley et al. used a package of bilingual and community-appropriate immunisation-promotion materials to support provider immunisation delivery. The intervention included credible sources, social support, and monitoring elements by using trained peer health educators and personalised immunisation outreach and promotion within social service and educational programmes. The intervention resulted in significantly increased immunisation coverage by 11.1% compared to the control, which had none of the intervention services. In addition, 53% of the intervention group were more likely to complete the immunisation series earlier (by 11 days, t = 3.91) compared to the control (adjusted odds ratio (AOR) = 1.53; 95% confidence interval (CI) = 1.33-1.75).

Several studies reported factors and predictors contributing to vaccination hesitancy. The main predictors of vaccine uptake were: history of sickness from past vaccination; knowing someone who became sick; fear of side effects; perceptions around importance and efficacy, such as the inability of vaccines to prevent flu; fear of needles; not wanting it; flu not considered a serious disease; and individuals not wanting to get the flu. Studies also examined barriers to vaccine uptake that affect ethnic minority communities, finding that the most significant ones included: limited knowledge and awareness of vaccination transmission, susceptibility, prevention ability, and the opportunity presented to avoid treatment. Poor understanding of the health system, language, cultural barriers, and poor doctor-patient relationships compound access issues in minority groups. The most significant facilitators identified were awareness of vaccination importance and schedule and encouragement or recommendation from healthcare workers (HCWs), which was more effective when the HCWs were people with whom they had an existing relationship.

Hence, despite intervention challenges, such as the high resource cost (financial cost and vaccine supply) needed to deliver some interventions, recommendations for future interventions in these studies included the need for additional resources to enhance social support, in addition to providing vaccine education that was locally and culturally relevant to the intended community. The most effective way of sharing information was visual modes of delivery, which enabled participants to identify with the characters in the resource. Also, it is important that messages are factual and emphasise the costs and benefits of vaccination, thereby showing that two-sided messages are viewed more credibly. Furthermore, having messages from credible sources like physicians did not always significantly increase vaccine awareness and intention to receive a vaccine, but, in combination with a trusted community representative, such as a church pastor, more community members can be motivated to consider taking vaccines.

Although mass media campaigns can reach a broad spectrum of any population, this review found that their effects remain modest, primarily because of intention-to-action gaps. This limitation can be addressed through the use of personalised reminders and prompts. Furthermore, mass vaccine clinic venues often do not suit some ethnic, cultural, or faith-based minority groups, especially where privacy and time are required for meaningful dialogue. Adapting existing services and guidelines to match community preferences - for instance, offering free services through community-based clinics compared to hospitals to deliver vaccines - emphasises the interrelationship between different intervention functions (incentivisation, environmental restructuring, enablement, and fiscal measures) and how using multi-intervention functions for vaccination services can improve the effectiveness of services provided.

The review findings suggest that increased awareness and knowledge sharing from credible sources have the potential to encourage the general public to get vaccinated, but this needs to be community focused. It is also essential to strengthen engagement and build trust with ethnic minority communities and to acquire a better understanding of how to support diverse groups by ensuring more meaningful inclusion through more culturally competent health systems. The use of behavioural science frameworks such as the COM-B model, BCW, and BCT can guide the development of interventions that are tailored to the motivational drivers and educational needs - and that reflect the socio-cultural context - of diverse communities. Table 6 in the paper outlines recommendations based on BCTs identified in this review that can be used to promote vaccine uptake in racial and ethnic minority communities.

In conclusion: "The relevance and effectiveness of vaccination strategies are critical for successful public health protection against infectious diseases. To optimise outcomes, all members of the population need to be engaged, and this includes racial and ethnic minority populations...To design effective interventions related to the approach identified in this review, strong support from government and healthcare organisations would be needed to institute tailored, culturally appropriate approaches, as there is no one-size-fits-all solution and vaccine strategies have to be adapted according to the different needs of the ethnic minority population."