A smartphone and wearable tool to manage anger after trauma (Shift): A micro-randomized trial

Shift is a just-in-time-adaptive intervention that has been co-designed with people who have experienced trauma and problem anger, as well as digital health experts and mental health professionals. Shift leverages ecological momentary assessments (EMAs) to determine an individual’s current anger state, and then delivers personalised cognitive behavioral components that focus on managing anger from a physiological, cognitive, or behavioral perspective. The intervention components of Shift leverage: 1) best practice approaches to manage anger rumination, improve unhealthy communication, and increase cognitive reframing; 2) an evidence-based method to decrease physiological arousal (i.e., cyclic sighing and isometric exercises) 3) circuit breakers for when anger is out of control; and 4) support for managing negative mood states after an anger outburst. EMAs are sent four times per day, within a personalised schedule, and three reminders to complete each EMA are sent within the hour. Each EMA takes less than 30 seconds to complete. Adherence is recorded via the number of EMAs completed throughout the 30 days. Shift tracks mood and anger triggers via self-report, provides external crisis support in the form of crisis helplines, and includes a virtual supportive Coach embedded in the app. The virtual Coach provides the welcome and rationale for the app, the voice overs for explaining skills, and supportive advice after an individual experiences an anger outburst. Accompanying the Shift app, users have the option of also using a wearable, that tracks sleep, activity, and stress levels, and alerts the user when stress levels are high. Users can then choose to open Shift and access the intervention components, if they want to. Participants will use their personal Android or iOS device to operate Shift. Wearable devices (Garmin activity trackers) will be provided to participants to monitor physiological stress and sleep. Those who do not choose to use the wearable will not track their sleep or stress through other methods. This study will conduct a micro-randomized trial to test Shift's effect on anger intensity at the next decision point. Every participant at each decision point (i.e., 4 EMAs per day) will be randomised with 0.5 probability to be shown a additional app content tailored to the anger state, and with 0.5 probability to be shown nothing.