An ACT-Based Physician-Delivered Weight Loss Intervention

The purpose of the present study was to conduct a pilot RCT to test the feasibility of a physician-delivered ACT-based intervention for emotional eaters with overweight/obesity against standard care at a network of weight loss clinics. Participants were randomized to receive either standard care at the clinics or the ACT intervention.

The purpose of the present study was to conduct a pilot RCT to test the feasibility of a physician-delivered ACT-based intervention for emotional eaters with overweight/obesity against standard care at a network of weight loss clinics. Psychology clinical PhD students trained physicians in the delivery of the brief manualized intervention and were available for regular consults. The intervention consisted of eight, 5-10 minute sessions that could be easily incorporated into the physician's current practice. Over the duration of the ACT intervention, physicians met individually with patients to teach them various techniques to address and improve mindfulness, acceptance, and values clarification and commitment, all of which emotional eaters have been found to struggle with (Forman & Butryn, 2014). The proven habit formation technique of if-then planning (Gollwitzer, 1993) was used throughout these sessions in order to train emotional eaters to habitually use ACT techniques and to change the maladaptive habit of eating in response to negative emotions.

Participants were blind to their condition, but physicians and administrative staff were not blind to participant condition. Physicians were not blind to participant condition because they were responsible for delivering the ACT intervention or standard care. They were thus required to know the participant's condition in order to deliver the adequate treatment. Administrative staff was responsible for providing physicians with this information and organizing study paperwork and thus needed to be aware of participant condition as well.

Participants in the standard care condition were provided with diet and exercise counselling and psychoeducation from their physicians over the course of 8 sessions, as was routinely done at the clinic. Standard care did not involve any targeted intervention to reduce emotional eating.

In addition to receiving standard care, participants in the ACT condition were taught techniques to reduce their emotional eating. Three overarching skills were taught over the course of the ACT intervention: (1) values clarification and commitment, (2) metacognitive awareness, and (3) distress tolerance. Throughout the sessions, physicians formed if-then plans with the patients to specify how to habitually use the ACT techniques to reduce emotional eating in their everyday lives. At the end of each session, participants were given a one-page homework sheet that asked them to monitor their behavior and their use of the ACT techniques during the week.

Assessed by the Dutch Eating Behavior Questionnaire (DEBQ) emotional eating subscale. Scores range from 1 (never) to 5 (very often). Lower scores reflect lower emotional eating. This subscale score is calculated by taking the mean of all items on the subscale. Negative change scores reflect decreases in emotional eating.

Assessed by the Dutch Eating Behavior Questionnaire (DEBQ) external eating subscale. Scores range from 1 (never) to 5 (very often). Lower scores reflect lower external eating. This subscale score is calculated by taking the mean of all items on the subscale. Negative change scores reflect decreases in external eating.

Assessed by the Dutch Eating Behavior Questionnaire (DEBQ) restraint eating subscale. Scores range from 1 (never) to 5 (very often). Lower scores reflect lower restraint eating. This subscale score is calculated by taking the mean of all items on the subscale. Positive change scores reflect increase in restraint eating.

Assessed by the Distress Tolerance Scale (DTS). All items were rated on a 5-point Likert scale from 1 (strongly agree) to 5 (strongly disagree). The score is calculated as the mean of all items. Higher scores reflect higher levels of distress tolerance. Positive change scores reflect increases in distress tolerance.

Assessed by the Philadelphia Mindfulness Scale (PHLMS). All items were rated on a 5-point Likert scale from 1 (never) to 5 (very often). The subscale score is calculated as the sum of all items on the subscale, with the minimum possible score being 10 and the maximum possible score being 50. Higher scores reflect higher levels of awareness. Negative change scores reflect decreases in mindfulness and positive change scores reflect increases in mindfulness.

This questionnaire was developed for the present study to evaluate participants' real world application of the intervention. Participants were asked to indicate their level of agreement on a 5-point scale (1 = strongly agree and 5 = strongly disagree) to prompts such as "My values motivate me to lose weight" and "I am able to accept negative emotions and don't have to eat when I'm feeling bad". Total score was calculated as the mean of all items. Lower scores indicate higher values clarification. Negative change scores reflect increases in ACT application and values clarification.

Assessed by a self-developed questionnaire with items such as "the program reduced my emotional eating" and "the program was easy to follow". Scores represent mean ratings on a 5-point Likert-type rating scale from 1 (strongly agree) to 5 (strongly disagree). Lower scores reflect higher treatment satisfaction.

Assessed by a self-developed questionnaire with items such as "ease of difficulty" and "required preparation time". The following questions were assessed on Likert scales from 1 (to little) to 5 (too much) with middle scores (3) reflecting perceived balance (e.g., not too difficult, the right amount of preparation time). Total score was calculated as the mean of all items.

Each physician was asked to complete this questionnaire once during their administration of the ACT intervention (from July 2016 to February 2017)

Percentage of individuals who were eligible to participate in the study (based on the initial prescreen) that actually enrolled.

Inclusion Criteria: Only participants considered to be emotional eaters, as assessed by a score of 3.25 or higher on the Dutch Eating Behavior Questionnaire (DEBQ), were recruited for the study (van Strien, Herman, Anschutz, Engels, & de Weerth, 2012). Exclusion Criteria: Not being an emotional eater. Participants who did not speak, write, and read in English fluently were excluded from the study, as well as those who were pregnant.

Study data, including the intervention manual, study protocol, statistical analysis plan, and outcomes will be shared with other researchers upon request.