A Randomized Controlled Trial Testing a Digital, Gamified Early Intervention for Eating Disorders ("FlexED")

Change from Baseline in the Body Image - Acceptance and Action Questionnaire (BI-AAQ)

Self-report measure of body-image psychological flexibility. The measure consists of 13 (full measure) or 5 (short measure) items that ask about the degree to which thoughts and feelings about the body interfere with living. Higher scores indicate greater flexibility/adaptability.

Time frame: Baseline, 4, 8, 12, 24, 36, 48 weeks

Change from Baseline in the Body-Image Stroop Bias Score

Change in reaction time to body-related versus neutral words in an emotional stroop paradigm. In this paradigm, participants identify the color of the written word as quickly as possible. Differences in reaction time between emotionally relevant words and neutral words is calculated as a bias score. Lower bias scores indicate improvement.

Time frame: Baseline, 8 weeks, 24 weeks

Change from Baseline in Eye Gaze Fixations - Body-Image Related Images

Change in the number of fixations on body-image related images, including idealized bodies, overweight bodies, body-weight measurement, and images of binge eating and body-related distress. Fewer fixations indicate improvement.

Time frame: Baseline, 8 weeks, 24 weeks

Acceptability of the intervention

Enrollment targets met, \>70% of participants that start the intervention will complete \>80%, \>70% of participants and sessions will have user inputs indicating engagement.

Time frame: 8 weeks

Change from Baseline in Eating Disorder Examination (EDE)

Clinician-administered interview assessing eating disorder symptom severity, producing a Global score (main outcome) and 4 Subscale scores: Restraint, Eating Concerns, Weight Concerns, Shape Concerns. Higher scores indicate greater symptomatology.

Time frame: Baseline, 12 weeks, 24 weeks

Change from Baseline in the Eating Disorder Examination - Questionnaire (EDE-Q)

Questionnaire format of the clinician-administered interview assessing eating disorder symptom severity, producing a Global score (main outcome) and 4 Subscale scores: Restraint, Eating Concerns, Weight Concerns, Shape Concerns. Higher scores indicate greater symptomatology.

Time frame: Baseline, 12, 24, 36, 48 weeks

Change from Baseline in the Clinical Impairment Assessment (CIA)

Measures the extent to which eating disorder symptoms impair functioning. Higher scores indicate greater impairment.

Time frame: Baseline, 12, 24, 36, 48 weeks

Change from Baseline in the Comprehensive Assessment of Acceptance and Commitment Therapy Processes -10 (CompACT-10)

A 10-item measure of psychological flexibility as a multidimensional construct with subscales of Openness, Awareness and Engagement. Higher scores indicate greater flexibility/adaptability.

Time frame: Baseline, 4, 8, 12, 24, 36, 48 weeks

Change from Baseline in Daily Levels of Body Image Distress and Psychological Flexibility

4 days of ecological momentary assessment of 1) distress/body-image distress 2) problematic behaviors to change body weight/shape, 3) general attempts to suppress/get rid of unwanted thoughts and feelings, 4) avoiding doing things because of concern about body, and 5) the ability to maintain adaptive distance and 6) orient to values. Scaled items are on a Likert Scale 1=Not at All to 6=Very Much. For items 1-4, higher scores are more problematic; For items 5-6, higher scores are more flexible adaptive.

Time frame: Baseline, 8 Weeks