Iris Kanera

20 Chapter 1 AIM AND OUTLINE Part I. Intervention development Chapter 2 describes a particular part of the needs assessment that explores lifestyle-related details using a cross-sectional survey study. The aim of this study was to gain specific insight into cancer survivors’ lifestyle behaviors in the Netherlands, the prevalence and correlates of smoking, physical activity, alcohol, and fruit and vegetable consumption, the correlations between the different lifestyle behaviors, and the correlates of adherence to lifestyle recommendations. Chapter 3 describes the systematic development of the KNW, including detailed information and exploration of the underlying needs, program goals, performance objectives, changeable determinants, theoretical methods, intervention design, and the evaluation of the intervention. Part II. Intervention process evaluation Chapter 4 includes a process evaluation exploring how the intervention was used, appreciated, and whether use and appreciation were predicted by certain user characteristics. Furthermore, the adherence to an automated personalized ‘Module Referral Advice’was evaluated that aimed to guide participants through the intervention. Moreover, it was investigated whether the broad content was sufficiently tailored to suit the needs of a varied population of cancer survivors. Part III. Intervention effect evaluation The effects of the KNW intervention on lifestyle-related outcomes were evaluated in a randomized controlled trial, six and 12 months after completing the baseline assessment. The study in Chapter 5 describes the overall intervention effects of the KNW on vegetable, fruit, whole grain bread, and fish consumption, PA, and smoking behavior 6 months after baseline. Furthermore, the effect of using behavior-specific modules on the corresponding behavior was explored. Chapter 6 explores whether previously determined positive changes after six months were maintained in the long term (i.e., after 12 months). In accordance with the effect evaluation after six months, the effects of using the behavior-specific modules on outcomes of the corresponding behavior were explored. To identify possible subgroups that might benefit most from the web-based KNW, we evaluated whether possible intervention effects were moderated by socio-demographic variables.