Online Imaginal Exposure Therapy for Eating Disorders Trial

The goal of this clinical trial is to learn if an imaginal exposure intervention first conducted by Levinson and colleagues (2020) can produce similar promising results in individuals with anorexia on the waiting list of an NHS eating disorder service. The main question it aims to answer is:

1. How effective is Imaginal Exposure Therapy in reducing eating disorder symptoms and increasing weight in patients with AN?

   The secondary research questions are:
2. How effective is Imaginal Exposure Therapy in reducing anxiety and fear related outcomes around food and eating?
3. How effective is Imaginal Exposure Therapy in improving patients' general anxiety and depression symptoms?

Researchers will compare the results of individuals in the treatment condition to individual's in the control condition to explore the efficacy of the intervention on eating disorder and eating disorder fear symptomology, and body weight.

Participants in the intervention group will receive 4 sessions of online exposure therapy, and participants in the control group will remain on the waiting list with treatment as usual (primarily nurse monitoring).

Study design type: The study will have a parallel group design. Approximately half of the participants will be randomised to receive our intervention, IE for AN. The other half will remain on the waitlist for the service and receive treatment as usual (TAU), which includes specialist nurse monitoring, occasional medical reviews, and dietetic support (depending on the individual's particular needs). This study design will allow us to directly assess the efficacy of the IE intervention, as compared to standard waiting list monitoring, on participants' weight and AN symptoms.

Sampling: Potential participants will be identified by the direct care team; any details not obtained through the study questionnaires will be obtained through digital medical records. The researchers will request information where needed through the direct care team. Participants will be recruited through the NELFT ED service post referral triage, while patients are on the waiting list. Participants will be the adults on the waiting list for receiving AN treatment at NELFT.

Procedure: Following informed consent, participation in the trial will last 5 weeks.

Week 1: All participants will, where possible, come to the service in-person to be weighed. All participants will complete a set of psychometric questionnaires during this appointment. The IE group will also complete the Eating Disorder Fear Interview (Levinson et al., 2019), administered in order to identify a fear to target in exposure therapy. If not possible to attend in-person, this primary appointment will be held on Zoom. All baseline appointments will be with a study coordinator.

Week 2: First online imaginal exposure. Week 3: Second online imaginal. Week 4: Third online imaginal exposure. Week 5: Fourth online imaginal exposure and participants will complete the final battery of online questionnaires. They will then come to the service in-person to be weighed again.

Eligibility Criteria:
Inclusion Criteria:

* Patients on the North East London Foundation Trust Eating Disorder waiting list.
* Patients who are over the age of 18 years old.
* Patients of all genders.
* Patients who have a primary diagnosis of Anorexia Nervosa.
* Patients who are willing and able to provide written informed consent.

Exclusion Criteria:

* Patients on the waiting list who are under the age of 18.
* Females who are pregnant, planning pregnancy or breastfeeding.
* Patients involved in concurrent research which is likely to interfere with the imaginal exposure intervention.