CBT-based Online Self-help Training to Reduce Fear and Distress After Cancer (CAREST Randomized Trial): 24 Months Follow-up Using Latent Growth Models and Latent Class Analysis

BACKGROUND Psychological distress (PD) and fear of cancer recurrence (FCR) are common consequences of surviving cancer. Online self-help training could help many cancer survivors deal with PD and FCR at low costs. PURPOSE To evaluate the long-term effectiveness of the CAncer REcurrence Self-help Training (CAREST trial) to reduce PD and FCR. Moreover, to evaluate the relation between FCR and PD across time and identify subgroups representing different change trajectories in FCR over time and their predictors. METHODS This multicenter randomized controlled trial included 262 female breast cancer survivors, assigned to online self-help training or care as usual. Participants completed questionnaires at baseline and four times during the 24-month follow-up. The primary outcomes were PD and FCR (Fear of Cancer Recurrence Inventory). Latent growth curve modeling (LGCM) and repeated measures latent class analysis (RMLCA) were performed, both according to the intention-to-treat principle. RESULTS LGCM showed no differences between the average latent slope in both groups for both PD and FCR. The correlation between FCR and PD at baseline was moderate for the intervention group and strong for the CAU group and did not significantly decrease over time in both groups. RMLCA revealed five latent classes and several predictors of class membership. CONCLUSIONS We did not find a long-term effect of the CBT-based online self-help training in reducing PD or FCR, nor in their relation. Therefore, we recommend adding professional support to online interventions for FCR. Information about FCR classes and predictors may contribute to improvement of FCR interventions.