Processes and Outcomes of Cognitive Therapy vs. Cognitive Therapy + Exposure for Eating Disorders: Study protocol for a Randomized Controlled Trial

Cognitive Behavioural Therapy (CBT) has shown to be an effective treatment for various Eating Disorders. However, since approximately 30% of patients do not (or insufficiently) respond to treatment there is room for improvement. When taking a closer look at the protocols that are currently being used in clinical practice, it can be concluded that existing protocols often have a relatively strong focus on diet management. More emphasis on the cognitive aspects of CBT might make treatment more effective. Furthermore, there are indications that specific exposure elements (e.g. cue exposure, forbidden foods exposure, and positive body exposure) might be effective as well. Combining cognitive interventions with these exposure exercises might therefore also increase treatment effects. These ideas were leading ground for designing the current RCT. In this study, 106 adults with an Eating Disorder (BN, BED, and ED NOS) will receive psychotherapy (CT or CT + Exposure) in an outpatient mental health clinic in the Netherlands. Treatment consists of 20 individual sessions of 60 minutes (3 pre-sessions, 16 treatment sessions, 1 booster session). Primary outcome is severity of eating disorder pathology. Secondary outcomes include self-esteem, body satisfaction, mood, general psychological distress, craving, impulsivity and BMI. In addition, measures of various potential mechanisms of change are included. Assessments are taken at baseline, pre- and post-treatment, prior to-, during- and after each therapy session, and at 1, 6, 12 and 24 months follow-up. By including repeated measures of clinical outcomes and multiple potential process measures over the course of 2.5 years, we aim to examine both the clinical effects (acute and long-term) of both interventions, as well as the causal pathways that lead to therapeutic change.

CT + (Cue) Exposure is more effective than Pure CT (both in short- and long-term).

Intake; pre- and post-treatment; prior to-, during- and after each therapy session; and at 1, 6, 12 and 24 months follow-up.

Cognitive Therapy
Cognitive Therapy + (Cue) Exposure