Statistical analysis
REGRESSION
First, using the chi-square test, one-way analysis of variance, and the Kruskal–Wallis test, we compared the participants’ characteristics among the four groups that were stratified according to message allocation. Second, ordinal logistic regression analyses were conducted to examine intergroup differences in attitudes and intentions. We performed the analyses separately according to engagement or non-engagement in social participation activities by using a two-step modeling strategy: Model 1, without adjustment, and Model 2, with covariates fully controlled. For people with engagement in social participation activities, the type of activity was also controlled in Model 2. The results are presented as odds ratios (ORs) with 95% confidence intervals (CIs). All analyses were performed using IBM SPSS Statistics 29 (IBM Corp., Armonk, NY, USA).