Analysis of social combinations of COVID-19 vaccination: Evidence from a conjoint analysis

Using a conjoint analysis based on Japanese cases, this study attempts to identify a preferable social strategic combination of who are vaccinated, who are not, and who are waiting. Using two surveys that relied on quota sampling reflecting the Japanese demographic composition (n = 1024 & n = 2975), the results of the descriptive analysis show that the most preferred strategy at the individual level was wait-and-see, allowing for a risk assessment of side effects. Via conjoint analysis, I also found that participants who recalled blood relatives as their familiar entities tended to prefer a wait-and-see strategy for themselves and their blood relatives. The results of these analyses suggest that wait-and-see strategies for vaccination are preferred in Japan, making it difficult to achieve early herd immunity through vaccination.