Background Internet-based mental health interventions have been demonstrated to be effective in alleviating psychological distress and promoting mental well-being. However, real-world uptake and engagement of such interventions have been low. Rather than being stand-alone interventions, situating internet-based interventions under a stratified stepped care system can support users to continue with mental health practice and monitor their mental health status for timely services that are commensurate with their needs. A user-centered approach should be used in the development of such web-based platforms to understand the facilitators and barriers in user engagement to enhance platform uptake, usability, and adherence so it can support the users’ continued adoption and practice of self-care for their mental health. Objective The aim of this study was to describe the design process taken to develop a web-based stratified stepped care mental health platform, TourHeart+, using a user-centered approach that gathers target users’ perceptions on mental self-care and feedback on the platform design and incorporates them into the design. Methods The process involved a design workshop with the interdisciplinary development team, user interviews, and 2 usability testing sessions on the flow of registration and mental health assessment and the web-based self-help interventions of the platform. The data collected were summarized as descriptive statistics if appropriate and insights are extracted inductively. Qualitative data were extracted using a thematic coding approach. Results In the design workshop, the team generated empathy maps and point-of-view statements related to the possible mental health needs of target users. Four user personas and related processes in the mental health self-care journey were developed based on user interviews. Design considerations were derived based on the insights drawn from the personas and mental health self-care journey. Survey results from 104 users during usability testing showed that the overall experience during registration and mental health assessment was friendly, and they felt cared for, although no statistically significant differences on preference ratings were found between using a web-based questionnaire tool and through an interactive chatbot, except that chatbot format was deemed more interesting. Facilitators of and barriers to registering the platform and completing the mental health assessment were identified through user feedback during simulation with mock-ups. In the usability testing for guided self-help interventions, users expressed pain points in course adherence, and corresponding amendments were made in the flow and design of the web-based courses. Conclusions The design process and findings presented in the study are important in developing a user-centric platform to optimize users’ acceptance and usability of a web-based stratified stepped care platform with guided self-help interventions for mental well-being. Accounting for users’ perceptions and needs toward mental health self-care and their experiences in the design process can enhance the usability of an evidence-based mental health platform on the web.

BACKGROUND Internet-based mental health interventions have demonstrated to be effective in alleviating psychological distress and promoting mental well-being. Rather than being standalone interventions, situating Internet-based interventions under a stratified stepped care system can support users to continue with mental health practice and to monitor their mental health status for timely services that are commensurate with their needs. User-centered approach should be used in the development of such online platform to enhance uptake, usability, and adherence so it can support users’ continued adoption and practice of self-care for their mental health. OBJECTIVE The aim of this study was to describe the iterative design process taken to develop an online stratified stepped care mental health platform, TourHeart+, using user-centered approach to incorporate target users’ perceptions and feedback. METHODS The process involved a co-creation workshop with the interdisciplinary development team, user interviews, two usability testing sessions on the online guided self-help interventions of the platform and the flow of registration and mental health assessment, and a card sorting activity on chatbot topics and information architecture of the platform. Data collected from the workshop, usability testing, and card sorting were analyzed inductively and summarized as descriptive statistics if appropriate. The interviews were transcribed and analyzed by NVivo 12. RESULTS In the co-creation workshop, the team generated possible psychological needs of target users and three archetypes of chatbot for the platform. Three main themes and 8 subthemes were identified based on user interviews and four user personas were developed. In the usability testing for guided self-help interventions, 14 feedback and corresponding amendments were made. Results of the survey collected from 104 users during usability testing on registration and assessment found no significant differences on preference ratings between using an interactive online questionnaire tool (namely typeform) and through a chatbot. Facilitators and barriers of registering the platform and completing the mental health assessment were identified through users’ feedback during simulation with mock-ups. Participants’ impressions on the platform included being friendly, being cared for, accepting, and professional. Based on findings of the card sorting sessions, the 27 chatbot topics were revised and grouped under 6 new categories instead of 7 predetermined categories to better match with users’ perceptions and understanding. Some of the page titles of the platform were renamed; filtering tabs and more visual cues were added to improve the congruence between users’ perceptions and the platform structure. CONCLUSIONS The iterative process and findings presented in the study are important in developing a personalized platform to optimize users’ acceptance and usability of an online stratified stepped care platform with guided self-help interventions for mental well-being. This design process facilitated the integration of technology, existing scientific evidence, users’ experiences of the platform, and users’ real-life experiences.