Introduction: Mental health is in global jeopardy and devising effective preventative and curative solutions are vital. Lifestyle interventions have been shown to be efficacious for improving mental health; however, in a progressively digital culture, face-to-face (F2F) interventions are being replaced by online and mobile options.¹ While online delivery can overcome ‘hurdles’ of inaccessibility and may also be more ‘scalable’, it poses unique challenges, as decreasing levels of human support can affect adherence to lifestyle interventions and associated outcomes.^2,3,4 Research is needed to better understand the importance of human support in online interventions and the type and dosage of human support required to optimise adherence and outcomes.⁵

Aim: To determine the influence of graded levels of human support on the adherence to and outcomes of an online, multimodal lifestyle intervention targeting mental health.

Methods: The online intervention will be administered to a total of 360 participants who will be randomised into three equal groups: standard (S) which includes automated emails and helpdesk support; standard plus personalised SMS support (S+pSMS); and, standard plus a weekly online group discussion via videoconferencing (S+OGD). Measures of mental health, including the Depression Anxiety and Stress Scales (DASS-21), the ‘mental health’ and ‘vitality’ sub-scales from the Short Form Health Survey (SF-36) and the ‘Flourishing’ scale, will be taken at baseline, ten weeks and twenty weeks. Outcome measures will be compared across each ‘arm’ and stratified analysis will be utilised to explore the influence of demographic variables. Adherence will be explored through mixed methods.

Outcomes: The proposed study will provide a better understanding of the influence of human support on the adherence to, and outcomes of, online lifestyle interventions, which will inform best practice for the design of online interventions