Better App: (Further-)Development and Evaluation of a Digital Lifestyle Programme

In recent years, we developed and evaluated personalised lifestyle interventions, the BETTER programmes (BETER in Dutch, acronym for Move, Eat, Change). Underlying principle for all BETER programmes is that people with the same condition may have different underlying causes, so-called subtypes. In this follow-up project with a mixed methods design, we aim to evaluate and optimise the subtype-questionnaire/algorithm (study 1, interrater reliabiliy) and evaluate the digitised BETER programme, the BETTER App (study 2, case series design with qualitative and quantitative evaluation). The main questions it aims to answer are: 1. What is the inter-rater reliability of two subtype experts and criterion validity of the symptom questionnaire compared with the experts for identifying overweight subtypes? 2. How is the BETER app used and rated (process evaluation)? To answer question 1, participants complete a questionnaire and have two interviews with two experts. To answer question 2, participants use the BETTERapp for 6 weeks and complete a usability questionnaire after 3 and 6 weeks and participate in 1 or 2 focus group interviews. This study contributes to optimising the Minimal Viable Product of the BETER app to finally reach a mature version.