An Interdisciplinary eDelphi Study for the Conceptual Validation and Refinement of a Narrative-Based Engagement Framework in Preventative Digital Mental Health

Digital mental health interventions increasingly use narrative, game design, personalisation and behavioural data to support engagement, but it remains unclear how these features can be integrated without weakening fidelity to the original evidence-based intervention approach. This study examined interdisciplinary perspectives on a narrative based serious game and meaningful engagement framework for preventative digital mental health grounded in Self Help Plus (SH+) and Acceptance and Commitment Therapy (ACT) informed principles. A two-round electronic Delphi (eDelphi) study was conducted involving participants from Human-Computer Interaction (HCI), mental health experts, and representatives of the target user groups. Fifteen participants completed Round 1 and following attrition, twelve completed Round 2. Consensus required at least 70% agreement or disagreement and an interquartile range of no more than 1. Round 1 assessed agreement with core framework assumptions and established consensus on 6/12 items. Round 2 re-rated the six unresolved items with controlled feedback, introduced five clarification items and elicited refinement priorities. Round 1 showed broad support for narrative, game design, behavioural observation, transferability and flexible pacing, but identified tensions around translation of SH+/ACT principles, oversimplification, narrative complexity, behavioural data sufficiency, context specificity and autonomy. Round 2 produced consensus that SH+/ACT principles can be translated into interactive mechanics when the core SH+/ACT content and processes remain stable and adaptation occurs mainly through delivery style, examples, pacing, narrative framing and interaction format. Participants also supported adjustable narrative depth, multidimensional engagement assessment, principle level transferability and guided autonomy. The framework received partial conceptual support, but findings indicate that further development should proceed through a modular minimum viable product (MVP) and empirical testing rather than immediate deployment.