Effectiveness of a Stress Reduction Intervention for Disordered Eating Behaviours

Brief name: Stress reduction intervention. The intervention will involve a series of brief 3-5 minute stress reduction activities that are delivered via a smartphone application ('app'). These activities are audio files which included guided meditations, breathing exercises, thought defusion (letting go of thoughts), body scans, and gratitude exercises. There will be two intervention groups: guided and self-guided. Once access to the app is provided, participants in both groups will be able to access the stress-reduction activities whenever they choose. However, it is recommended that participants use these activities at times when they are feeling stressed. Participants in the guided intervention group will also receive personalised prompts to remind them to use the app; these are delivered when participants report they are at least moderately stressed. This reporting occurs via periodic surveys prompted through the same app; these are delivered 4 times per day at randomised times between the hours of 9am to 9pm for the four week duration of the study. The survey comprises only one question ("How stressed are you right now?"). Participants in the self-guided intervention group will also complete this monitoring and have access to the stress-reduction activities to use whenever they choose, however they will not receive any personalised reminders. The intervention phase of the study will last for four weeks. Participants' use of the intervention will be monitored through the app, in which participants will be asked to respond to a brief one-item survey prior to and after using a stress-reduction activity. As the activities are delivered via the app, it is not possible to directly assess fidelity. Adherence will be promoted through provision of a variety of different exercises to allow participants to engage with those they find most helpful and reduce the likelihood of disinterest due to repetition.