key: cord-0792286-oio6y0q1
authors: Knight, H.; Jia, R.; Ayling, K.; Bradbury, K.; Baker, K.; Chalder, T.; Morling, J. R.; Durrant, L.; Avery, T.; Ball, J.; Barker, C.; Bennett, R.; McKeever, T.; vedhara, k.
title: Understanding and Addressing Vaccine Hesitancy in the Context of COVID-19: Development of a Digital intervention
date: 2021-03-26
journal: nan
DOI: 10.1101/2021.03.24.21254124
sha: 446d8c81732f575dd542b9e39a7314dff3188487
doc_id: 792286
cord_uid: oio6y0q1

Background Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) was identified in late 2019, spreading to over 200 countries and resulting in almost two million deaths worldwide. The emergence of safe and effective vaccines provides a route out of the pandemic, with vaccination uptake of 75-90% needed to achieve population protection. Vaccine hesitancy is problematic for vaccine rollout; global reports suggest only 73% of the population may agree to being vaccinated. As a result, there is an urgent need to develop equitable and accessible interventions to address vaccine hesitancy at the population level. Method We report the development of a scalable digital intervention seeking to address COVID-19 vaccine hesitancy and enhance uptake of COVID-19 vaccines. Guided by motivational interviewing (MI) principles, the intervention includes a series of therapeutic dialogues addressing 10 key concerns of vaccine hesitant individuals. Development of the intervention occurred linearly across four stages. During stage 1, we identified common reasons for COVID-19 vaccine hesitancy through analysis of existing survey data, a rapid systematic literature review, and public engagement workshops. Stage 2 comprised qualitative interviews with medical, immunological, and public health experts. Rapid content and thematic analysis of the data provided evidence-based responses to common vaccine concerns. Stage 3 involved the development of therapeutic dialogues through workshops with psychological and digital behaviour change experts. Dialogues were developed to address concerns using MI principles, including embracing resistance and supporting self-efficacy. Finally, stage 4 involved digitisation of the dialogues and pilot testing with members of the public. Discussion The digital intervention provides an evidence-based approach to addressing vaccine hesitancy through MI principles. The dialogues are user-selected, allowing exploration of relevant issues associated with hesitancy in a non-judgmental context. The text-based content and digital format allow for rapid modification to changing information and scalability for wider dissemination.

The digital intervention provides an evidence-based approach to addressing vaccine hesitancy through MI principles. The dialogues are user-selected, allowing exploration of relevant issues associated with hesitancy in a non-judgmental context. The text-based content and digital format allow for rapid modification to changing information and scalability for wider dissemination.

All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in The copyright holder for this this version posted March 26, 2021. ;  https://doi.org/10.1101/2021.03.24.21254124 doi: medRxiv preprint

Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) was identified in late 2019. At the time of writing, the latest estimates suggest that it has spread to over 200 countries and has resulted in the deaths of almost two million people.

[1] The resulting global pandemic has seriously affected the social and economic fabric of societies everywhere and the physical and mental health crisis continues. [2] Safe and effective vaccines provide a route out of this crisis, but the development of these vaccines, while necessary, are not sufficient. For vaccines to achieve their full potential, the public also need to be willing to be vaccinated. Recent data suggest this cannot be assumed. A recent international survey indicated that, globally, 73% of the population would agree to being vaccinated.

[3] This estimate should be viewed against a backdrop of declines in vaccine intent overall and the fact that it masks large variations in intent between countries, genders and across age and ethnic groups. [3] [4] [5] Vaccine hesitancy, defined as a "delay in acceptance or refusal of vaccines despite availability of vaccine services" [6] may significantly impact uptake of COVID-19 vaccines, particularly amongst ethnic minorities, women, and those with less education [7] . If, as has been suggested, 75-90% of a population will need to be vaccinated for community protection to be achieved, [8] then there is an urgent need to develop equitable and accessible interventions to address vaccine hesitancy at the population level.

Attempts to improve vaccine uptake are not new and have focussed traditionally on approaches such as information/education, incentives [9] [10] [11] and reminders. However, results from successive reviews suggest that the evidence-base in support of any one approach remains limited. [9] [10] [11] [12] Furthermore, much of the work has been conducted in the context of All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in The copyright holder for this this version posted March 26, 2021. ;  https://doi.org/10.1101/2021.03.24.21254124 doi: medRxiv preprint adults making decisions for their dependents, rather than adults making decisions for themselves. The generalisability of these findings to COVID-19 vaccines in adults is, therefore, unclear. Nonetheless, much can be gleaned from the existing evidence:

information, while necessary, is unlikely to improve vaccine uptake on its own, and interventions need to engage with individuals' reasons for hesitancy i.e., their hesitancy cognitions. [13] We report here on the development of a scalable digital intervention which seeks to address the concerns of individuals who are vaccine hesitant with a view to enhancing the uptake of COVID-19 vaccines. We report the process we followed in developing a digital vaccine hesitancy intervention suitable for adults considering a COVID-19 vaccination. In view of the urgency of the public health need, our approach to intervention development was pragmatic and took advantage of existing data where possible and appropriate.

Our development involved four main stages and included involvement of public and patient partners throughout:

Stage 1: In order to understand and identify common reasons for COVID-19 vaccine hesitancy and acceptance we carried out a) an analysis of existing survey data collected during the pandemic, b) a rapid systematic literature review and c) an examination of qualitative findings from a series of public engagement workshops regarding immune challenges and vaccines. Stage 2: We synthesised evidence from independent experts. This entailed qualitative interviews with experts from a range of relevant disciplines to identify evidence-based responses to the most common vaccine concerns raised by the public identified in stage 1. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in As this was a linear process with each stage informing the next, we present the methods and results from each stage consecutively.

Stage 1: Understanding and identifying common reasons for hesitancy & acceptance.

As part of an ongoing longitudinal study [14] into the UK population's mental and physical health over the course of the pandemic, we collected data regarding COVID-19 vaccination intention between 11 th -30 th November 2020. This included whether participants intended to get the vaccine and a free text response to elaborate on their main reasons for this intention.

Free text responses were analysed for common themes and the frequency at which these themes appeared was quantified. Where vaccine hesitancy was indicated, themes were also categorised within the WHO 3Cs model of vaccine hesitancy, which proposes that three main factors influence the decision to accept vaccines: confidence, complacency, and convenience (WHO, SAGE, 2014). [6] Coding and categorisation was conducted independently by two researchers (RJ, KA) with high levels of initial agreement (91% for reasons associated with vaccine hesitancy and 85% for reasons associated with agreement to vaccination). All discrepancies were resolved by discussion.

A total of n=762 individuals provided data (22% of whom indicated they were hesitant about receiving a COVID-19 vaccination); 93% (n=709) of respondents also provided a free-text response indicating their reasons for vaccine acceptance or hesitancy, of which 96% (n=683) provided sufficient detail for reasons to be categorised into themes. For those who expressed All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in vaccine hesitancy, the most common concerns were found to map on to the WHO 3C category of 'confidence' (e.g., concerns related to long term complications, side effects and insufficient testing of the vaccines). The second most common concerns related to 'complacency' (e.g., beliefs of low personal risk of COVID-19, beliefs in ability to fight off the infection naturally). Concerns related to the 'convenience' category were the least common, and centred on a lack of information about the vaccines and altruism (i.e., other people needing the vaccines more) (see Table 1a ). In contrast, in respondents who indicated they would be willing to receive a COVID-19 vaccine, the common reasons given related to 'self-protection', followed by 'hope to end the pandemic/wish for normal life' and a desire to 'protect the population or unspecified others and control the virus' (see Table 1b ).

All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in "I would take any vaccine at this point" "Can't think of a good reason why not to take it"

To identify additional themes/reasons for COVID-19 vaccine hesitancy that may have not been captured in our survey, a rapid systematic literature review was conducted. Four electronic databases (Medline, PsychInfo, Medrxiv, PsyAxiv) were searched to identify peerreviewed journal articles and pre-prints which examined reasons for COVID-19 vaccine hesitancy dated between 01/01/2020 and 03/12/2020: using the following search terms:

(COVID-19 vaccine hesitancy) OR ((COVID-19) AND (Vaccine hesitancy)). One researcher (RJ) conducted abstract and full-text screening to determine eligibility and a second crosschecked all eligibility decisions (KA).

Following title and abstract screening, 49 articles remained for full-text screening, with 10 ultimately deemed suitable for inclusion summarised in table 2 [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] . The primary reason for excluding articles at the full-text screening stage were that many studies looked at vaccine intention only, not reasons for vaccine hesitancy (see Figure 1 ). Three of the studies were The most common themes identified in this review mirrored those identified in our survey.

However, the following additional themes were identified: (1) vaccine scepticism; (2) cost of vaccines;

(3) concerns relating to vaccine contents; (4) timing of vaccination in relation to the state of the pandemic and (5) concern that the vaccine might result in COVID-19 disease (see table 2 ).

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perpetuity.

preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in The majority of the COVID-19 vaccine related concern were long term side effects and insufficient knowledge about the vaccine. Other concerns included: short term side effects (e.g., fever), vaccine effectiveness and general anti-vaccine attitudes. Concerns about vaccine safety (100%) centred on the newness of the vaccine and its safety (e.g., long-term effect, side effects) and effectiveness.

a Themes or responses were based on participants who provided information on vaccine hesitancy.

To ensure we captured the views of ethnic minority groups on COVID-19 vaccines, we also consulted PPI findings available through the University Hospital Southampton NHS Foundation Trust PPI team regarding the acceptability of vaccines. Several PPI meetings were held on this broad area between July-October 2020, including meetings that specifically sought the views of Black and Minority Ethnic (BAME) individuals.

The feedback from all the consultation meetings was reviewed and was found to reveal considerable overlap in the vaccine concerns identified in these meetings, with those identified as part of our survey and literature review. The only additional concerns related to whether vaccines had been tested on people from different ethnic groups and issues of trust in the medical and scientific communities. These issues were, therefore, prioritised for inclusion in our intervention.

hesitancy.

The evidence emerging from the survey, rapid literature review and PPI findings was then triangulated through discussion between the behavioural scientists contributing to this stage of the work. The aim of these discussions was to identify the most common COVID-19 vaccine concerns. This was based in part on the frequency with which concerns were identified in the survey, review, and PPI findings; ensuring that all three domains of the WHO 3C model were represented and that any unique perspectives raised by ethnic minority participants were also captured.

This led to the identification of nine core COVID-19 vaccine concerns. In keeping with the most frequently cited concerns being related to 'confidence', 5/9 concerns related to 'confidence' (i.e., generalisability of evidence on vaccine safety and effectiveness to diverse All rights reserved. No reuse allowed without permission.

perpetuity.

preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in populations; side-effects; rapid nature of vaccine development; clinical effectiveness and vaccine scepticism). Two out of ten concerns related to 'complacency' (i.e., low perceived risk of COVID-19 and belief in ability to fight off the infection naturally). A further two concerns related to 'convenience' (i.e., perceived lack of knowledge about COVID-19 vaccine and altruistic beliefs regarding others having a greater need). A tenth concern was subsequently added when the UK government decided to alter the dosing schedule from 3/4 weeks to up to 12 weeks between the two doses recommended for the Astra Zeneca and Pfizer vaccines. In keeping with the WHO 3C model, this latter issue also related to the issue of 'confidence'.

Following the identification of 10 core vaccine concerns (Table 3) we sought to gather evidence-based responses to these concerns. This was achieved through semi-structured interviews with six academic and clinical experts from the fields of public health, general medicine, respiratory medicine and immunology with particular expertise in COVID-19 and/or COVID-19 vaccines. Each expert was presented with the list of 10 concerns and asked to provide an evidence-based response to each concern based on their knowledge of the scientific literature at that time. Interviews with experts were subjected to rapid thematic and content analysis after each interview and interviews continued until saturation in responses was achieved (i.e., no new responses emerged) [25] .

The expert responses demonstrated significant thematic overlap and consistency. Table 3 summarises the areas of evidence cited by experts in response to each concern. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in • The data suggests short-term protection of at least 3 months All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in • Whilst many people experience mild symptoms, COVID-19 is unpredictable; we are not able to predict who will be adversely affected.

• Although COVID-19 affects older people most severely, a significant proportion of those hospitalised are under the age of 60.

• We know that you can contract COVID-19 more than once and are unsure how long any immunity to the virus lasts after exposure.

• The vaccines offer protection against the virus and prevent the risk of experiencing a severe form of the disease.

• Receiving a vaccine could prevent you from requiring hospitalisation.

• Vaccination reduces the volume of the population who can contract and spread the virus, reducing the disease burden in the community. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in • It is also possible to get re-infected with the virus, although evidence suggests the reinfection results in less severe illness.

• The immune system can exhibit extreme reactions to the COVID-19 virus, but it is very unlikely to react in such a way to the vaccines.

• Reducing your risk of contracting and therefore spreading COVID-19 helps to protect others.

• Reducing your risk of contracting COVID-19 also means you are much less likely to need to selfisolate. • Effectiveness has been shown in individuals of all ages, ethnic backgrounds, and with other health conditions.

• No serious side effects have been reported; participants in the early trials have now been monitored for almost 12 months.

All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in "Other people need it more than me"

• The Joint Committee for Vaccines and Immunisations (JCVI) has identified a priority list for vaccine dissemination.

• If someone is offered a vaccine, it means they have been identified as being in a priority group. • This decision was taken because it allows twice as many people to get some protection against the virus, offering the greatest opportunity to save lives.

• The first vaccination offers short term protection, whilst the second booster dose provides longer term protection.

• Delaying the second dose from 3 to 12 weeks also gives the immune system longer to develop immunity.

• In the Oxford-AstraZeneca vaccine trials, a longer gap between doses offered better protection. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in MI was considered an appropriate approach because individuals who are vaccine hesitant are, by definition, not ready to, or ambivalent about, changing their cognitions and behaviour and MI is known to be effective in such contexts. [27, 28] Thus, for each of the most common vaccine concerns identified in Stage 1 we developed a therapeutic dialogue which would both impart information relevant to the individual concern, but do so using the communication principles of MI with a view to facilitating cognitive and, in turn, behaviour change i.e., reduce hesitancy and improve vaccine uptake.

Development of the therapeutic dialogues occurred through several expert workshops with behavioural scientists with expertise in MI, therapeutic interventions, digital interventions, All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in The copyright holder for this this version posted March 26, 2021. ; https://doi.org/10.1101/2021.03.24.21254124 doi: medRxiv preprint behaviour change and COVID-19. First, key themes identified in the expert interviews (Stage 2) were discussed and translated into conversational language. The investigators chose a conversational approach to align with the online delivery format and to ensure inclusivity for all reading/English levels (see stage 4 below). Second, the dialogues were reviewed to identify points at which MI techniques could be integrated throughout. This process drew on contributors' experience in behaviour change research and adopted the approach proposed by Rollnick and colleagues [26] . This included expressing empathy through use of accepting and non-judgemental language. Developing discrepancy by simultaneously providing information related to the concern, and presenting a rationale for vaccine uptake. The latter were derived from survey respondents willing to accept a COVID-19 vaccine (see Table 1b ) and sought to develop a discrepancy between the individual's cause for concern and their wider personal values and goals. Embracing resistance by acknowledging that their concerns are shared by others and are legitimate and supporting self-efficacy by reinforcing the individual's personal agency in making their decision to accept a vaccine or not. See Table 4 for illustrative examples of how MI principles were embedded within the therapeutic dialogues. Finally, we hosted a PPI workshop to discuss the resulting dialogues. The group, while small (n=4), included two adults less than 30 years (two greater than 50 years); three women and one man and all reported an interest in vaccine hesitancy and had some experiences of it in friends and family. The feedback obtained through this workshop fostered changes to their readability, along with expansion of the information conveyed and greater consideration of specific groups within the population (i.e. those who have allergies or specific religious and cultural needs). No additional vaccine concerns were identified by the group.

The script from each of the 10 therapeutic dialogues provided the architecture for our digital, web-based, vaccine hesitancy intervention. This intervention has been built in the form of a conversational interface through which individuals identify the issue that most closely underpins their reason for being hesitant, (from the issues stated above e.g., concerns about side effects). This identification triggers a therapeutic dialogue relevant to the selected concern, with opportunities for the individual to further explore the content as they progress through the dialogue as well as to access responses to more than just their initial concern.

Once developed, the digital intervention was piloted with 18 members of the public (nine male / nine female) who had no previous experience with the dialogues. Participant feedback All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in 

The development of safe and effective vaccines against SARS CoV-2, while necessary, will not be sufficient to contain COVID-19 unless we also achieve high vaccine uptake. We have described here the rapid development of an evidence-based digital intervention which draws on the communication principles of MI and is in keeping with many of the recommendations made in a recent review of approaches to increasing vaccine uptake e.g., focus on the concerns of the population. [29] Our aim is to provide the end-user with an intervention which is individualised to their specific concerns, acknowledges the legitimacy of these concerns, provides up to date information related to these concerns whilst also providing an accepting non-judgemental context in which they can explore their reasons for hesitancy. The textbased content and digital format mean it can be readily scaled-up for wider dissemination and rapidly modified for implementation in different languages and to respond to changing information.

Although this intervention, like much else to do with COVID-19, has been developed at pace we think the process highlights some potential issues regarding intervention development worthy of discussion. First, the development of our digital, behavioural intervention followed a fairly conventional path as outlined in the Medical Research Council's (MRC) best practice guidance. This involved evaluating the evidence base and theory as well as incorporating the views of target users [30] . This was possible partly because we had timely access to PPI findings available through the University Hospital Southampton NHS Foundation Trust All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in A critical step in digital intervention development is optimisation of intervention content, since digital intervention content cannot be adjusted 'in the moment', like in a practitioner delivered intervention. We were able to conduct optimisation work with PPI, albeit with a smaller sample (N=4) than might usually be employed in digital intervention development.

Computer science methodology states that during intervention optimisation around 80% of views can be captured with five target users and we were close to this threshold [31] .

However, best practice guidance from digital health psychology suggests including larger, diverse samples is important to ensure views of people from different backgrounds are considered [30] . Despite having a smaller sample, our optimisation with PPI did help us to improve the persuasiveness and accessibility of the key messages within the intervention. It is possible that we may have found other important ways of optimising our content by including a larger, more diverse group of PPI at this stage. However, it is important to note that this intervention is quite simple, it targets only one behaviour, draws on a very well-established behavioural technique which guided content design (MI), and it addressed barriers that were thoroughly identified using existing evidence in the intervention planning stage. Therefore, in this particular context, it is possible that sufficient optimisation was achieved with a smaller sample.

The MRC highlights the importance of making use of existing data and evidence wherever possible. In this work, we were able to benefit from data collected as part of another study [14] where we were able to identify specific concerns related to vaccine hesitancy. We also drew on evidence kindly shared with us by others. This allowed acceleration of the intervention development and improved the economic efficiency of research. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in In view of the urgency of the public health issue we conducted a rapid review. Indeed, COVID-19 has most likely led to an unprecedented number of rapid reviews, as the scientific community have clamoured to understand the available evidence as quickly as possible.

Although, it is clear that rapid reviews take many forms (e.g., limited by language, dates, databases etc.), they do vary in the quality of their reporting and the methodological shortcuts they take. [32] The implications of these inconsistencies for the quality and validity of these reviews is, however, unclear as there is thus far limited evidence comparing the results of different review approaches. The provision of such evidence in future research would undoubtedly inform the contexts in which it is appropriate to conduct rapid reviews, and the methods that should be employed. Such guidance now exists for scoping reviews [33] and would appear to be in development for rapid reviews by the Equator network.

[34]

In summary, for COVID-19 vaccines to achieve their full public health potential, the public need to be willing to be vaccinated. Recent data suggest this cannot be assumed. We have reported here on the development of a scalable digital intervention which seeks to address the concerns of individuals who are vaccine hesitant with a view to enhancing their confidence in COVID-19 vaccines and, in turn their uptake. The effects of the intervention on these outcomes will be the subject of future work. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in 

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We would like to thank Dr Lucy Fairclough (University of Nottingham), Dr Simon Royal (University of Nottingham), and Dr David Turner (University of Nottingham) for their contributions to the expert interviews.All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in 

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in