Content Adaptations and Usability Improvements in a Brazilian Digital Mental Health Platform: Lessons Learned from Iterative User-Centered Research

Introduction: Digital mental health interventions are especially relevant in low- and middle-income countries, where access to face-to-face care is limited. However, many platforms insufficiently incorporate user experience, reducing engagement and effectiveness, particularly among vulnerable populations. Methods: This study adopted an exploratory mixed-methods approach conducted across four sequential phases to improve a Brazilian digital mental health platform focused on anxiety and stress management. Data were collected from four sources: focus groups with 36 community leaders from a low-income urban area; surveys with 36 highly educated users; think-aloud usability interviews with 10 participants; and an online survey with 102 young adults. Qualitative and quantitative data were integrated to identify design and content gaps. Results: Participants consistently reported the need for culturally resonant language, shorter and more dynamic videos, greater diversity among presenters, and improved visual design and accessibility. These findings guided platform adaptations, including revised audiovisual formats, updated language and imagery, and enhanced accessibility features. The results reinforce the importance of user-centered and culturally sensitive design in digital mental health tools, particularly in socially diverse contexts. Conclusion: Findings suggest that user-centered adaptation processes can help improve the usability and cultural relevance of digital mental health interventions.