Aim: The aim of the study was to investigate how young adult survivors of childhood cancer used an online discussion forum as part of a web-based psycho-educational intervention. Specifically, we aimed to characterize users of the discussion forum, investigate how they used the discussion forum (type of usage) and content of the posted messages.

Methods: This study is a part of a randomized controlled trial, Fex-Can Childhood RCT. Participants with self-reported sexual dysfunction or fertility-related distress were drawn from a population-based national cohort. Sociodemographic and clinical characteristics of the intervention group (n = 322) and data on usage of the discussion forum were analysed with descriptive statistics and compared between subgroups. Messages posted in the online discussion forum were analysed with qualitative thematic analysis.

Results: Approximately half (48 %) of participants in the intervention group accessed the discussion forum and most of them (76 %) without writing own posts. Users of the discussion forum did not statistically differ in sociodemographic or clinical characteristics from the rest of the intervention group. The 97 written posts, written by 38 individuals, were mainly descriptions of own experiences and thoughts and concerned three themes: A changed body, Concerns around family building and Longing for support. Peer-support and interaction between participants were seen in some forum threads and the 'like'-function was frequently used, demonstrating engagement and activity. Participants expressed that they felt affinity with and appreciated sharing own experiences and to recognize themselves in others' stories.

Conclusions: A discussion forum as part of a web-based intervention appears to be a valuable component by giving participants an opportunity to share intimate experiences and concerns related to surviving cancer.