Adapting Exposure for Adolescent AN

The Eating Disorder Examination Questionnaire (EDE-Q) is a 28-item self-report questionnaire. It was designed to assess the range, frequency, and severity of behaviors associated with a diagnosis of an eating disorder. A global score is obtained by summing the four subscales scores (ranging from 0-6) and dividing the total by the number of subscales (4). The score of items are calculated and range from 0 to 6. The higher score indicate greater ED symptoms.

The Fear of Food Measure (FORM) is a 23-item self-report questionnaire. It examines the participant's severity of behaviors associated with a diagnosis of an eating disorder. Each item is scored on a 1-7 scale. The questionnaire range from 23 to 161 meaning 23: no fear of food and 161 meaning severe fear of food.

The BSQ is a self-reported measurement of the body shape concerns typical of bulimia nervosa and anorexia nervosa. The questionnaire has 34 items scored from 0 to 6 points (least and most impaired, respectively), with the sum of the questions giving a range from 0 to 204. The higher score indicates greater concerns about body shape.

The Clinical Impairment Assessment Questionnaire (CIA) is a 16-item self-report measure of the severity of psychosocial impairment due to eating disorder features and focuses on the past 28 days. The 16 items cover impairment in domains of life that are typically affected by eating disorder psychopathology: mood and self-perception, cognitive functioning, interpersonal functioning, and work performance. The responses are scored 0,1,2 and 3, with a higher rating indicating a higher level of impairment. The total range is between 0 and 48.

The Eating Disorder Fear Questionnaire (EDFQ) is a 20-item self-report questionnaire. It examines the participant's severity of behaviors associated with a diagnosis of an eating disorder. The response range between 1 to 7 with a total range of 20 to 140. The higher rating indicates a higher severe impairment.

The Weight Gain Anxiety Questionnaire is a 12-item self-report questionnaire that targets anxiety about weight gain. The scores are measured on a 0-100 scale, with the higher the score indicating more distress about weight gain, with the exception for question 2 which is reverse scored.

The Eating Gain Anxiety Questionnaire is a 14-item self-report questionnaire that targets anxiety about eating fear foods. The scores are measured on a 0-100 scale, with the higher the score indicating more distress about eating fear foods, with the exception for question 2 which is reverse scored.

The Patient Health Questionnaire-9 is a 9-item self-report questionnaire that targets depressive symptoms. The scores range from 0-27, with higher scores indicating a higher level of depression.

The Generalized Anxiety Disorder-7 is a 7-item self-report questionnaire that targets anxiety symptoms. The scores range from 0 to 21, with higher scores indicating higher levels of anxiety.

Eating Disorder Examination - Self-Report Questionnaire Parent Version 1.5 (PEDE-Q) is a 29-item self-report questionnaire. It is intended to be completed by the parent of a child with an eating disorder targeting the parent's perspective of their child's eating disorder. It was designed to assess the range, frequency, and severity of behaviors associated with a diagnosis of an eating disorder. A global score is obtained by summing the four subscales scores (ranging from 0-6) and dividing the total by the number of subscales (4). The score of items are calculated and range from 0 to 6. The higher scores indicate greater perceived child's ED symptoms.

The Parent vs Eating Disorder Scale (PVED) is a 7-item self-report questionnaire that examines parents' opinions on parent involvement in the treatment of their child's eating disorder. Higher scores indicate higher agreement with the statements, and lower scores indicate lower agreement with the statements. Scores range from 1 (strongly disagree) - 5 (strongly agree).

We will measure the participants' weight using a wireless smart scale.

The Treatment Acceptability Questionnaire is a 10-item self-report questionnaire. It examines the participants' perspective on the modules in the exposure therapy. The response range between 1 to 7, with a total range of 10 to 70. The higher rating indicates a higher rating of treatment acceptability.

We will measure recruitment by calculating the percentage of eligible participants approached who consent to the study. The higher the percentage, the more successful we were with recruiting for the study.

We will measure the percent of participants who complete the study by calculating the percentage of participants that complete the three-month follow-up. The higher the percentage, the more participants completed the study.

We will measure participant engagement by calculating the number of sessions participants attend out of 20 total sessions. The higher the number of sessions attended, the more participant engagement in the study.

We will measure the therapists' adherence to the protocol by completing a treatment adherence measure that measures the study interventionists' adherence to the protocol. The higher the treatment adherence measure, the more the study interventionists adhered to the protocol.