Accepted for/Published in: Journal of Medical Internet Research
Date Submitted: Sep 9, 2025
Date Accepted: Mar 9, 2026
Warning: This is an author submission that is not peer-reviewed or edited. Preprints - unless they show as "accepted" - should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.
Development and Evaluation of Educational Messages and Notifications for the OA Coach Mobile Application: A Knee Osteoarthritis Self-Management Intervention
ABSTRACT
Background:
The OA Coach mobile application (app) is a digital self-management tool to support people with knee osteoarthritis (OA).
Objective:
To optimize notifications and educational messages within the OA Coach app using behaviour change theory and co-design, motivating users to adopt long-term positive lifestyle choices.
Methods:
This was a mixed-methods study using focus groups and online surveys. We worked with consumers, health professionals, and researchers to refine daily call-to-action and encouragement notifications for the OA Coach app. Clarity, comprehensibility, and motivational impact were assessed through an online survey using 1-5 Likert scales and free text responses. We also co-designed weekly educational messages based on recommendations from international OA clinical practice guidelines. Data from three focus groups and a survey were used to guide selection of message topics, timing, clarity and language for motivational impact.
Results:
Eighty notifications were refined to enhance clarity, engagement, and effectiveness in prompting meaningful actions by future OA Coach users. Key themes guiding modifications included reducing technical jargon, simplifying colloquial expressions, and removing language perceived to be patronizing or frustrating. Fourteen educational messages were co-designed to ensure the messages were relevant, supportive, and empowering.
Conclusions:
Evidence-based notifications and educational messages, underpinned by behaviour change theory and international guideline recommendations, were iteratively co-designed and refined in collaboration with consumers, health professionals and researchers. These notifications and messages were integrated into the OA Coach app to optimise engagement, support behaviour change, and promote uptake of recommended care for knee OA. The updated OA Coach app is currently being evaluated in the COASTAL trial, comparing face-to-face, telehealth, and digitally delivered models of care for knee OA. Practice Points: 1. Digital tools such as OA Coach can improve access to evidence-based OA self-management by delivering targeted education and behavioural support aligned with international guidelines. 2. The application of behaviour change theory, combined with iterative co-design involving consumers, health professionals, and researchers, is essential for developing engaging and actionable notifications and educational messages in digital health interventions.
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