MOODS

Commercial wearables from Fitbit, Garmin, and Whoop have recently introduced real-time notifications based on detecting changes in physiological responses indicating potential stress. In this paper, we investigate how these new capabilities can be leveraged to improve stress management. We developed a smartwatch app, a smartphone app, and a cloud service, and conducted a 100-day field study with 122 participants who received prompts triggered by physiological responses several times a day. They were asked whether they were stressed, and if so, to log the most likely stressor. Each week, participants received new visualizations of their data to self-reflect on patterns and trends. Participants reported better awareness of their stressors, and self-initiating fourteen kinds of behavioral changes to reduce stress in their daily lives. Repeated self-reports over 14 weeks showed reductions in both stress intensity (in 26,521 momentary ratings) and stress frequency (in 1,057 weekly surveys).

In conjunction with the mProv Collaborative Project, we

successfully deployed the Mobile Open Observation of Daily Stressors (MOODS) study with real-world participants, completing data collection in Summer 2022. To reach this stage, we secured approvals from both major app stores (Google and Apple) for the MOODS app, including implementing required customizations for Apple.

The participant enrollment process was fully developed, starting with an initial screening survey sent to targeted groups as outlined in the IRB procedures. Eligible participants were placed in a candidate pool for bi-weekly enrollment. Upon selection, they received an invitation email with app store download links. The MOODS app guided participants through the informed consent process, after which we received their personal information and shipped them a study watch, completing enrollment.

The app also included weekly surveys. To enhance engagement, we developed a visualization and explanation pipeline that compiled participant stress data into graphical summaries. These were sent weekly before the surveys, allowing participants to review and provide feedback on their stress patterns.

Additionally, we created back-end data monitoring tools for researchers to track study progress and individual participation. These tools helped diagnose potential failures, ensuring timely interventions to maximize data completeness.