Location, location, location: a discrete choice experiment to inform COVID-19 vaccination programme delivery in the UK.

BACKGROUND: Large-scale vaccination is fundamental to combatting COVID-19. In March 2021, the UK's vaccination programme had delivered vaccines to large proportions of older and more vulnerable population groups; however, there was concern that uptake would be lower among young people. This research was designed to elicit the preferences of 18-29-year-olds regarding key delivery characteristics and assess the influence of these on intentions to get vaccinated, to inform planning for this cohort. METHODS: From 25 March to 2 April 2021, an online sample of 2012 UK adults aged 18-29 years participated in a Discrete Choice Experiment. Participants made six choices, each involving two SMS invitations to book a vaccination appointment and an opt-out. Invitations had four attributes (1 × 5 levels, 3 × 3 levels): delivery mode, appointment timing, proximity, and sender. These were systematically varied according to a d-optimal design. Responses were analysed using a mixed logit model. RESULTS: The main effects logit model revealed a large alternative-specific constant (ß = 1.385, SE = 0.067, p < 0.001), indicating a strong preference for 'opting in' to appointment invitations. Pharmacies were dispreferred to the local vaccination centre (ß = - 0.256, SE = 0.072, p < 0.001), appointments in locations that were 30-45 min travel time from one's premises were dispreferred to locations that were less than 15 min away (ß = - 0.408, SE = 0.054, p < 0.001), and, compared to invitations from the NHS, SMSs forwarded by 'a friend' were dispreferred (ß = - 0.615, SE = 0.056, p < 0.001) but invitations from the General Practitioner were preferred (ß = 0.105, SE = 0.048, p = 0.028). CONCLUSIONS: The results indicated that the existing configuration of the UK's vaccination programme was well-placed to deliver vaccines to 18-29-year-olds; however, some adjustments might enhance acceptance. Local pharmacies were not preferred; long travel times were a disincentive but close proximity (0-15 min from one's premises) was not necessary; and either the 'NHS' or 'Your GP' would serve as adequate invitation sources. This research informed COVID-19 policy in the UK, and contributes to a wider body of Discrete Choice Experiment evidence on citizens' preferences, requirements and predicted behaviours regarding COVID-19.

Efficacy or delivery? An online Discrete Choice Experiment to explore preferences for COVID-19 vaccines in the UK.

COVID-19 vaccines are widely regarded as an integral component in the UK's pandemic recovery, and a comprehensive distribution strategy will be required to maximise uptake. However, to date, there is a dearth of research into factors that could lead to UK residents' acceptance or rejection of COVID-19 vaccines. This study used a discrete choice experiment to investigate the importance of vaccine properties, delivery and media coverage in amplifying or attenuating vaccine uptake. Efficacy was found to be the factor that most influenced vaccine selection; further, the positive effect of high efficacy was more pronounced for those aged 55+. Insights from this DCE aim to assist policymakers and public health communicators in planning and refining their delivery strategy for COVID-19 vaccines.