Date of Award


Embargo Period


Degree Type


Degree Name

Doctor of Philosophy (PhD)




Faculty of Nursing and Health

First Advisor

Associate Professor Darren Morton

Second Advisor

Dr Jason Morton


4203 Health services and systems| 4206 Public health


Escalating mental health distress has prompted the call for mental health promotion initiatives to improve the mental resilience of the general population and provide a buffer against common mental health disorders. Digital delivery modes offer accessible and scalable opportunities to implement lifestyle-based interventions to enhance mental well-being. However, digital interventions are hampered by sub-optimal adherence, which negatively impacts outcomes. Little is known about the effectiveness of human support to improve adherence to and outcomes of digital interventions amongst general population cohorts.

This dissertation documents the rationale for and findings of a randomised comparative study that assessed the influence of adding different types of human support to an online, interdisciplinary mental health promotion intervention. Participants were randomised into three intervention groups: standard intervention with automated emails only (S); standard intervention plus personalised text messages (S+pSMS); and standard intervention plus videoconferencing support (S+VCS). A questionnaire was administered pre- and post-intervention to assess changes in depression, anxiety, stress, mental health, vitality, life satisfaction, and flourishing. Adherence was measured by the number of video lessons viewed, points scored for experiential activities, and the number of weeks that participants logged activity. Inductive, thematic analysis of free-text responses in the post-intervention questionnaire elicited participant perceptions about facilitators and barriers impacting adherence. The study results led to a series of three publications, which addressed the three research questions presented in the dissertation and a fourth publication that consolidated the findings and reviewed them in the context of the current literature.

The first publication addressed Research Question 1—What is the influence of different modes of human support on the outcomes of a web and mobile app, lifestyle-based mental health intervention for a healthy adult cohort? This publication found that human support had little influence on the outcomes of the intervention. Significant improvements were recorded from baseline to post-intervention in every outcome measure, irrespective of the types of human support offered (P≤0.001). Between-group differences were not observed for any of the outcome measures: depression (P=0.93), anxiety (P=0.25), stress (P=0.57), mental health (P=0.77), vitality (P=0.65), life satisfaction (P=0.65), and flourishing (P=0.99).

The second publication addressed Research Question 2—What is the influence of different modes of human support on attrition and adherence to a web and mobile app, lifestyle-based mental health intervention for a healthy adult cohort, including the influence of participant preference? Early dropout attrition differed between the groups (P=.009), being disproportionally higher in the videoconferencing support group. However, there was no difference in adherence behaviour between the groups (i.e., number of videos viewed, P=0.42; mean challenge points scored, P=0.71; and the number of weeks challenge points were logged, P=0.66), indicating that human support had little effect.

The third publication addressed the final research question—What do healthy adult participants perceive as the facilitators of, and barriers to, adherence to a web and mobile app, lifestyle-based mental health intervention? Qualitative thematic analysis revealed that human support did not feature strongly as a facilitator or barrier to intervention adherence. Perceived adherence facilitators included engaging content, time availability, accessibility, enjoyable challenges, valuing the program, and personal motivation. Time scarcity was overwhelmingly perceived as the most dominant adherence barrier. Other barriers included completing and logging experiential activity, content length, technical difficulties, and interindividual personal factors.

The study’s findings provided novel insights into an exposed research gap, as little was known about the influence of human support on adherence to and outcomes of a digital mental health promotion intervention when delivered to a general population group. The fourth publication, a review, synthesised the overall findings of this dissertation in conjunction with other recent literature and provided recommendations for future studies.


Used by permission: the author.

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