In the UK, over 4 in 5 Britons are worried about the effect COVID-19 is having on their life, with over half reporting that their wellbeing has been affected. Providing support for individuals to build optimal structures to maintain their physical and mental wellbeing is key to mitigate the consequences of the pandemic on day-to-day life and in the longer term. The investigators would like to conduct a randomised-controlled trial to test the efficacy of a theory-based self-management booklet to improve physical and mental wellbeing versus education alone. The trial will include a nested qualitative study to explore in a subgroup of participants their experiences of the self-management booklet or education alone. The primary objective is to examine the efficacy of the self-management booklet at improving wellbeing as compared to the waiting-list control arm 2-months post-randomisation. The investigators also want to explore the treatment effects of the self-management booklet on secondary outcomes (health status, day-to-day activities, resilience, intolerance of uncertainty, loneliness, social support, sleep quality, napping, sedentary behaviour, physical activity, and COVID-19-related behaviours, symptom complaints). Tertiary objectives include exploring changes in self-reported primary and secondary outcomes over time in a non-randomised analysis combining data from both arms and qualitatively exploring participants' perceptions of the acceptability and usefulness of the self-management booklet. These objectives will be addressed by a two-armed parallel randomised controlled trial (RCT) with a nested qualitative study. The study will be conducted through Qualitrics (including recruitment, randomisation, and data collection). Participants in both arms will be followed-up at 2 and 4 months post-randomisation. Additionally, participants in the control arm will receive the self-management booklet after the 4-months follow-up assessment and will be followed-up at 6 and 8 months post-randomisation.
