Effectiveness of enhanced cognitive behavioral therapy (CBT-E) for eating disorders: study protocol for a randomized controlled trial

Publication Type:

Journal Article


Trials, Volume 17 (2016)




eating disorders; CBT; RCT


Background: While eating disorder not otherwise specified (EDNOS) is the
most common eating disorder (ED) diagnosis in routine clinical
practice, no specific treatment methods for this diagnosis have yet been
developed and studied. Enhanced cognitive behavioral therapy (CBT-E)
has been described and put to the test as a transdiagnostic treatment
protocol for all EDs, including EDNOS. Initial research in the UK
suggests that CBT-E is more effective for EDs, especially bulimia
nervosa (BN) and EDNOS, than the earlier version of CBT. These positive
results of CBT-E have to be replicated in more detail, preferably by
independent researchers in different countries. Being the first Dutch
study into CBT-E, the results from this national multicenter study - on
three sites specialized in EDs - will deliver important information
about the effectiveness of CBT-E in several domains of ED pathology,
while providing input for the upcoming update of the Dutch
Multidisciplinary Guideline for the Treatment of Eating Disorders.

Methods/design: A multicenter randomized controlled trial will be
conducted. One hundred and thirty-two adult outpatients (aged 18 years
and older) with an ED diagnosis and a Body Mass index (BMI) of between
17.5 and 40 will be randomly allocated to the control or the
intervention group. Subjects in the control group will receive Treatment
as Usual (standard outpatient treatment provided at the participating
sites). Subjects in the intervention group will receive 20 sessions of
CBT-E in 20 weeks. The design is a 2 (group) x 5 (time) repeated
measures factorial design in which neither therapists nor patients will
be blinded for treatment allocation. The primary outcome measure is
recovery from the ED. Secondary outcome measures include ED
psychopathology, common mental disorders, anxiety and depressive
symptoms, health-related quality of life, health care use and
productivity loss. Self-esteem, perfectionism and interpersonal problems
will be examined as putative predictors and mediators of the effect of
treatment. Also, an economic evaluation from a societal perspective will
be undertaken. All relevant effects, direct and indirect costs will be
included. Utility scores will measure the effects. Measurements will
take place at pretreatment, 6 weeks, 20 weeks, 40 weeks and 80 weeks.

Discussion: This effectiveness study into CBT-E has the aim of
broadening the scope and generalizability of former studies. If CBT-E
appears to be at least as effective as traditional diagnosis-specific
treatments for a broad range of ED patients, training in one protocol
would be sufficient for clinicians to treat patients with different
kinds of EDs. It gives the opportunity to offer treatment for a severe
mental disorder with fewer resources, thereby increasing the
accessibility of specialized care for patients with an ED.