Bi-directional associations between mask usage and the associated reasons before and after the downgrading of the legal status of COVID-19 in Japan: A longitudinal study

ObjectivesFrom a public health perspective, it is important to clarify the associations between mask usage and the associated reasons in situations when mask usage is promoted or mitigated. Therefore, I clarified the changes in mask usage and the associated reasons before and after the downgrading of the legal status of COVID-19 in Japan, and analyzed the bi-directional associations between the two. DesignLongitudinal study. MethodsOnline surveys were conducted in two waves, between April 18-19, 2023 and June 6-15, 2023, among people aged 20-69 years living in Japan. A total of 291 participants completed both the surveys. The associations between mask usage and beliefs about the reasons for mask usage were analyzed using a cross-lagged panel model. ResultsMask usage decreased slightly, but significantly, from the first to the second wave (P < 0.001, Cohens d = -0.23). Of the eight beliefs regarding mask usage, slight but significant decreases were observed in terms of relief and information effects (P = 0.046, Cohens d = -0.12; P = 0.018, Cohens d = -0.14). There was a significant association between socio-psychological reasons other than infection risk avoidance (such as norm and relief) during the first wave and mask usage during the second wave [standard estimates:0.25 (95% confidence interval (CI):0.06-0.44)]. Contrarily, mask usage during the first wave was significantly associated with the reasons for infection risk avoidance during the second wave [standard estimates:0.13 (0.03-0.24)]. ConclusionsThe impact of downgrading the legal status of COVID-19 in Japan on mask usage and the associated reasons were found to be limited. In terms of promoting or mitigating mask usage, the significance of risk communication based on socio-psychological reasons other than infection risk avoidance, such as norms and relief, was highlighted.