Abstract: In recent years, Internet-based interventions have gradually been applied to improve the mental health of bereaved people, and systematically investigating the effectiveness of Internet-based interventions for bereaved people and the moderators helps guide clinical practice. In this study, 47 studies of Internet-based interventions for bereaved people were selected through literature search and screening, of which 19 randomized controlled trials met the criteria of meta-analysis (N = 1222). The meta-analysis included a total of 68 effect sizes. The results showed that the interventions had a significant moderate effect on mental health (g = 0.54; 95% CI = [0.39, 0.70]). Specifically, the interventions showed significant moderate effects for symptoms of pathological grief (g = 0.56; 95% CI = [0.39, 0.74]), depression (g = 0.51; 95% CI = [0.36, 0.67]), and posttraumatic stress disorder (g = 0.63; 95% CI = [0.45, 0.81]). For improving mental health, excluding meaning reconstruction, having 10 sessions or more, and therapeutic feedback was associated with a larger effect of the Internet-based interventions, and contacting more than once a week showed a stronger effect than once a week. However, whether an intervention was based on cognitive behavior therapy, set reminders, had a high or low dropout rate, included exposure exercises, cognitive reconstruction, or behavioral activation had no moderating effect. This study shows that Internet-based interventions have positive effects on improving the mental health of bereaved people and have different effects under different conditions.

Key words: bereavement, Internet-based intervention, pathological grief, posttraumatic stress disorder, depression