Introduction
breast) cancer, cancer, PD, breast cancer
CANCER, BREAST CANCER
Advances in the diagnosis and treatment of (breast) cancer have resulted in increased survival rates. As a result, there is an increasing group of breast cancer survivors that have to cope with the long-term consequences of cancer. Fear of cancer recurrence (FCR) is one of the most common long-term psychological consequences of surviving breast cancer [Given the burden of FCR and PD for cancer survivors, there is a need to develop (tailored) interventions to efficiently address FCR and also to reduce PD [In the current paper, we will evaluate the long-term effectiveness (>15 months) of this online self-help training in reducing both FCR and PD and identify subgroups representing different change trajectories in FCR over time and their predictors. To meet this aim, we use three longitudinal latent variable models, each focusing on a different research question. First, in a multi-group latent growth model, we will evaluate change in FCR and PD (research question 1; RQ1). We hypothesize greater FCR and PD reduction in the intervention group compared to CAU at 15 and 24 months. Second, in a multivariate multi-group latent growth model, we will evaluate the relation between FCR and PD at baseline and across time (research question 2; RQ2). We hypothesized a strong relation (