Prolonged grief disorder (PGD) is a chronic, impairing state of intense grief that is responsive to specialised intervention. Online journalling has the potential to reduce PGD symptoms.

To assess whether reminiscence via online journalling facilitates bereavement adjustment – specifically, to identify key themes in online grief journals and examine associations between types of reminiscence and changes in PGD symptom severity.

A cohort of 96 bereaved adults completed 7 days of online journalling on the Living Memory Home (LMH) bereavement website. Participants were recruited from clinics, bereavement support groups and a National Institutes of Health-funded, web-based platform. The Prolonged Grief Disorder-Revised scale (PG-13-R) was administered at baseline and at 1-week and 1-month follow-up.

Descriptive analysis revealed a reduction in PG-13-R scores from baseline to 1-week follow-up (mean difference −3.7, 95% CI: −4.9, −2.5, P < 0.001) and 1-month follow-up (mean difference −5.0, 95% CI: −6.4, −3.7. P < 0.001). Mixed-methods analysis revealed significant negative associations between reflection on negative traits of the deceased and PG-13-R score at all three time points, and between reflection on past experiences with the deceased and PG-13-R score at baseline. Expression of regret and guilt was significantly associated with reduction in PG-13-R scores from 1-week to 1-month follow-up.

Engagement in the LMH website demonstrated significant declines in PGD symptom severity after 1 week of online journalling and at 1-month follow-up. Guided reflection on memories of the deceased, and even on negative or emotionally challenging memories, shows potential for reducing symptoms of PGD.