BackgroundSelf-care behaviors are commonly prescribed to manage both cardiovascular disease and hypertension to reduce modifiable risk factors and improve quality of life. Nevertheless, long-term adherence to self-care recommendations for cardiac patients has been problematic. In cardiac patients, moderated online forums have been found to be particularly useful in supporting maintenance of heart-healthy diet and fewer hospital visits. As such, we developed the e-Forum, a Web-based moderated forum designed to promote continued user engagement and long-term self-care adherence.ObjectiveThe objective of this study was to assess the usability of the user interface for the newly designed e-Forum. In addition to overall user satisfaction, we obtained feedback from our target users on the key features of this newly developed interface.MethodsAn iterative design tested the usability of the e-Forum. On the basis of the user feedback, adjustments were made to the design of our e-Forum, and these changes were then tested in the succeeding group. Participants were recruited from the Heart Function Clinic at the Peter Munk Cardiac Center, University Health Network. After consenting to participate in our study, patients were asked to complete a set of goal-oriented tasks and a feedback interview for the e-Forum. A content analysis of the transcripts from the set of goal-oriented tasks and feedback interviews identified several themes, including general feedback and comments regarding 3 key areas of the e-Forum: layout, navigation, and content.ResultsOverall, 13 cardiac patients (aged 32-81 years) participated in 3 rounds of testing. Participants across all 3 rounds were highly satisfied with our e-Forum and indicated that they would find such a forum useful in managing their health. Expressions of overall satisfaction with the e-Forum and positive comments regarding layout increased between the initial and the final round. As improvements were made to the e-Forum based on participant feedback, potential barriers, negative comments related to the content, and the number of navigation errors decreased between rounds 1 and 3.ConclusionsWe found evidence to support the usability of the user interface for our e-Forum. These results indicate that the e-Forum will likely be a successful tool to support an online community of cardiac patients in their efforts to sustain long-term lifestyle behavior change.