Abstract

The present study examined whether perceived social support has a moderating, mediating, or additive effect on the process by which interpersonal stressful experiences could influence the course of depression over the following month and investigated the mediating effect of mattering within the process. Questionnaires were administered three times (t1, t2, t3) at two-week intervals. Based on the data from 86 participants with dropouts excluded, covariance structure models were estimated and their model fits, direct effects, and indirect effects were analyzed. Results revealed that the additive model, which hypothesized that interpersonal stressful experiences and perceived social support could independently influence the course of depression, was a better fit than moderating and mediating models. In the additive model, mediating effects of mattering were not significant in the relationship between interpersonal stressful experiences and depression (t1, t2, t3). However, t1 mattering showed significant mediating effects in the relationship between perceived social support and depression (t1, t2, t3). These findings indicate that perceived social support can be a protective factor against depression, independent of the severity of interpersonal stressful experiences, and that providing early intervention focused on mattering can be crucial. Limitations and implications of the present study are also discussed.