A Digital Health Platform to Support Self-Management of Hypophosphatasia in Adults (HPP Helper)

Enrolled participants will receive a pre-configured Amazon Echo Show 8 (DVA equipped with an 8-inch interactive HD touchscreen) delivered to their homes via courier. The unit will be shipped with written and visual onboarding materials detailing home Wi-Fi connection, microphone/camera privacy controls, basic touch and voice navigation commands, and contact details for the trial research team to provide dedicated remote setup support. Instructions on the use of the intervention software interface "BuddyLink" (Great Australian Pty Ltd) will also be provided. This interface can be accessed via the DVA, or via a web browser on other internet-enabled devices, as preferred by participants. Following baseline assessment, intervention content is provided across the 12-week intervention period on two days per week (generally Monday and Thursday). New educational videos, modules, and task prompts trigger visual on-screen notifications on the DVA, alerting participants to their availability. Participants can choose to interact with these immediately, or at a later date, using their preferred device. All newly unlocked modules remain permanently accessible on demand throughout the remainder of the 12 weeks for repeated viewing and ongoing reference. Live group sessions will be scheduled on days and times deemed most convenient for the majority of participants and conducted via Zoom. Recordings of these sessions will be shared via BuddyLink so that those who are unable to attend in person can review the content. The 12-week curriculum is developed based on current evidence and our previous co-design process with adult HPP consumers. Content includes: Educational Videos: Delivered by research team members and based on clinical practice guidelines, content covered will include “Understanding HPP” (biology, clinical phenotypes, and reviews of contemporary metabolic bone disease research). “Health Behaviours” (Instruction on resistance training, joint-protection ergonomics, fall mitigation, and pacing strategies designed to avoid stress fractures, guidance on whole-food nutrient density and anti-inflammatory diets, management of calcium and vitamin D intake), “Mental Health” (cognitive and behavioural self-management approaches to addressing diagnostic delay distress, chronic pain interference, illness uncertainty, and social isolation in rare diseases, and access to support services), and “Health Navigation” (guidance on building multidisciplinary care teams, accessing allied health and psychology treatment plans, and transitioning to sustainable community self-management). Personalised Health Tracking: The optional Digital Health Diary and Dietary Tracker allows participants to regularly record symptoms (e.g., pain, fatigue, mobility), healthcare appointments, and daily food logs. Aggregated personal diary summaries can be exported directly to the participant via email to inform clinical consultations. Noticeboard and Healthcare Professional Database: Accessible directly through the BuddyLink interface, the HPP Noticeboard functions as a shared repository of curated community resources, including educational content, physical activity options, healthy recipes, services and healthcare (e.g., general practitioners, endocrinologists, rheumatologists, and allied health professionals with adult HPP expertise) recommendations. Participants can nominate noticeboard content via the platform or email. All nominations undergo screening by the research team prior to being published and broadcast to the participant cohort. Group-Based Peer Interactions and Health Professional Education Sessions: Includes two live 60-minute investigator-facilitated peer connection videoconferences (conducted via Zoom in Week 2 and Week 12) to foster shared lived experiences, alongside an optional, asynchronous, study-moderated peer messaging group (linked via BuddyLink) available throughout the 12-week trial. Participants will also be invited to participate in a structured, live 60-minute clinical education seminar conducted via Zoom in Week 6 (with session recordings archived in Week 7 for on-demand access). The seminar will be delivered by a specialist endocrinologist/metabolic bone expert and cover multidisciplinary clinical management, research directions, and an interactive participant Q&A based on pre-submitted and live questions. Artificial Intelligence Question-and-Answer Tool: Participants will have on-demand access to "HPP AI," a conversational agent embedded within the DVA. The tool operates using the OpenAI ChatGPT API via an enterprise license, ensuring zero data retention (conversations are neither recorded nor used for model training). The agent is bounded by pre-specified guardrails and an evidence-based HPP knowledge base curated by the study investigators. It is programmed to answer general consumer queries regarding HPP, lifestyle modifications, and trial navigation, while explicitly restricting independent diagnostic claims and redirecting urgent clinical queries to the participant’s treating physician. Intervention engagement and adherence will be monitored objectively via BuddyLink server logs, tracking accessing of specific modules across the 12 weeks. Acceptable adherence is quantitatively defined as accessing =66% of delivered content. Platform usage data will be paired with automated conversational check-ins assessing content relevance and usefulness. Participants will be clearly instructed that platform materials support their health self-management and do not replace personalised advice from their medical team.