Research protocol for BootStRaP assessment phase: A nine-nation study on boosting societal adaptation and mental health in a rapidly digitalising, post-pandemic Europe

Background: There is increasing global concern about the harms associated with problematic usage of the internet (PUI) affecting young people. Various risk factors have been proposed, but there is a scarcity of reliable evidence on the extent of the problem, who is most at risk of developing PUI and why, and how best to tackle it. Objectives: BootStRaP (ISRCTN59576080) is a five-year multinational research programme designed to boost young people's health and resilience by determining, through prospective longitudinal assessment, the risk factors associated with PUI and its health economic impact and designing and testing preventative self-management interventions tailored to individual risk factors. Methods: This paper describes the first phase of the project (i.e., Cohort 1). A sample of over 2500 schoolchildren aged 12–16 years was recruited across nine European countries. They were prospectively monitored over a 6-month period using a dedicated smartphone application (BootstrApp), through which their internet use habits, health and wellbeing were measured. Young people were involved in the co-design of aspects of the protocol including the recruitment plan and elements of the app design. The components of the assessment battery were chosen to investigate specific individual, clinical, cognitive and environmental risk determinants as defined a priori in an evidence-based logic-model. Participants were assessed using a combination of standardised demographic and clinical questionnaires, ambulatory assessment techniques, cognitive testing and passive digital monitoring. Multimodal data is analysed according to machine learning and structured equation modelling. Expected outcomes: Our findings will contribute toward A) developing algorithms for predicting individuals at risk for PUI, B) identifying actionable variables for application to subjects as interventions for testing in the second phase of the project, C) validating risk hypotheses stated in the logic model of PUI including the interplay between predisposing risk factors (e.g., impulsivity, compulsivity), affective and cognitive processes (e.g., reward-related attentional biases), and executive functions (e.g., inhibitory control), D) calculating the health economic cost and impact of PUI in young people across Europe.