Mediators of change in cognitive behavior therapy and interpersonal psychotherapy for eating disorders: A secondary analysis of a transdiagnostic randomized controlled trial.

OBJECTIVE: Understanding the mechanisms of action of psychological treatments is a key first step in refining and developing more effective treatments. The present study examined hypothesized mediators of change of enhanced cognitive behavior therapy (CBT-E) and interpersonal psychotherapy for eating disorders (IPT-ED). METHOD: A series of mediation studies were embedded in a randomized controlled trial (RCT) comparing 20 weeks of CBT-E and IPT-ED in a transdiagnostic, non-underweight sample of patients with eating disorders (N = 130) consecutively referred to the service. Three hypothesized mediators of change in CBT-E (regular eating, weighing frequency, and shape checking) and the key hypothesized mediator of IPT-ED (interpersonal problem severity) were studied. RESULTS: The data supported regular eating as being a mediator of the effect of CBT-E on binge-eating frequency. The findings were inconclusive regarding the role of the other putative mediators of the effects of CBT-E; and were similarly inconclusive for interpersonal problem severity as a mediator of the effect of IPT-ED. DISCUSSION: This research highlights the potential benefits of embedding mediation studies within RCTs to better understand how treatments work. The findings supported the role of regular eating in reducing patients' binge-eating frequency. Other key hypothesized mediators of CBT-E and IPT-ED were not supported, although the data were not inconsistent with them. Key methodological issues to address in future work include the need to capture both behavioral and cognitive processes of change in CBT-E, and identifying key time points for change in IPT-ED.

Scaling Up Psychological Treatments: A Countrywide Test of the Online Training of Therapists.

BACKGROUND: A major barrier to the widespread dissemination of psychological treatments is the way that therapists are trained. The current method is not scalable. OBJECTIVE: Our objective was to conduct a proof-of-concept study of Web-centered training, a scalable online method for training therapists. METHODS: The Irish Health Service Executive identified mental health professionals across the country whom it wanted to be trained in a specific psychological treatment for eating disorders. These therapists were given access to a Web-centered training program in transdiagnostic cognitive behavior therapy for eating disorders. The training was accompanied by a scalable form of support consisting of brief encouraging telephone calls from a nonspecialist. The trainee therapists completed a validated measure of therapist competence before and after the training. RESULTS: Of 102 therapists who embarked upon the training program, 86 (84.3%) completed it. There was a substantial increase in their competence scores following the training (mean difference 5.84, 95% Cl -6.62 to -5.05; P<.001) with 42.5% (34/80) scoring above a predetermined cut-point indicative of a good level of competence. CONCLUSIONS: Web-centered training proved feasible and acceptable and resulted in a marked increase in therapist competence scores. If these findings are replicated, Web-centered training would provide a means of simultaneously training large numbers of geographically dispersed trainees at low cost, thereby overcoming a major obstacle to the widespread dissemination of psychological treatments.

Using the Internet to Train Therapists: Randomized Comparison of Two Scalable Methods.

BACKGROUND: One of the major barriers to the dissemination and implementation of psychological treatments is the scarcity of suitably trained therapists. The currently accepted method of training is not scalable. Recently, a scalable form of training, Web-centered training, has been shown to have promise. OBJECTIVE: The goal of our research was to conduct a randomized comparison of the relative effects of independent and supported Web-centered training on therapist competence and investigate the persistence of the effects. METHODS: Eligible therapists were recruited from across the United States and Canada. They were randomly assigned to 1 of 2 forms of training in enhanced cognitive behavior therapy (CBT-E), a multicomponent evidence-based psychological treatment for any form of eating disorder. Independent training was undertaken autonomously, while supported training was accompanied by support from a nonspecialist worker. Therapist competence was assessed using a validated competence measure before training, after 20 weeks of training, and 6 months after the completion of training. RESULTS: A total of 160 therapists expressed interest in the study, and 156 (97.5%) were randomized to the 2 forms of training (81 to supported training and 75 to independent training). Mixed effects analysis showed an increase in competence scores in both groups. There was no difference between the 2 forms of training, with mean difference for the supported versus independent group being -0.06 (95% Cl -1.29 to 1.16, P=.92). A total of 58 participants (58/114, 50.9%) scored above the competence threshold; three-quarters (43/58, 74%) had not met this threshold before training. There was no difference between the 2 groups in the odds of scoring over the competence threshold (odds ratio [OR] 1.02, 95% CI 0.52 to 1.99; P=.96). At follow-up, there was no significant difference between the 2 training groups (mean difference 0.19, 95% Cl -1.27 to 1.66, P=.80). Overall, change in competence score from end of training to follow-up was not significant (mean difference -0.70, 95% CI -1.52 to 0.11, P=.09). There was also no difference at follow-up between the training groups in the odds of scoring over the competence threshold (OR 0.95, 95% Cl 0.34 to 2.62; P=.92). CONCLUSIONS: Web-centered training was equally effective whether undertaken independently or accompanied by support, and its effects were sustained. The independent form of Web-centered training is particularly attractive as it provides a means of training large numbers of geographically dispersed therapists at low cost, thereby overcoming several obstacles to the widespread dissemination of psychological treatments.

The severity and status of eating disorder NOS: implications for DSM-V.

"Eating disorder NOS" is the most common eating disorder encountered in outpatient settings yet it has been neglected. The aim of this study was to describe the characteristics of eating disorder NOS, establish its severity, and determine whether its high relative prevalence might be due to the inclusion of cases closely resembling anorexia nervosa or bulimia nervosa. One hundred and seventy consecutive patients with an eating disorder were assessed using standardised instruments. Operational DSM-IV diagnoses were made and eating disorder NOS cases were compared with bulimia nervosa cases. Diagnostic criteria were then adjusted to determine the impact on the prevalence of eating disorder NOS. Cases of eating disorder NOS comprised 60.0% of the sample. These cases closely resembled the cases of bulimia nervosa in the nature, duration and severity of their psychopathology. Few could be reclassified as cases of anorexia nervosa or bulimia nervosa. The findings indicate that eating disorder NOS is common, severe and persistent. Most cases are "mixed" in character and not subthreshold forms of anorexia nervosa or bulimia nervosa. It is proposed that in DSM-V the clinical state (or states) currently embraced by the diagnosis eating disorder NOS be reclassified as one or more specific forms of eating disorder.

Assessing Therapist Competence: Development of a Performance-Based Measure and Its Comparison With a Web-Based Measure.

BACKGROUND: Recent research interest in how best to train therapists to deliver psychological treatments has highlighted the need for rigorous, but scalable, means of measuring therapist competence. There are at least two components involved in assessing therapist competence: the assessment of their knowledge of the treatment concerned, including how and when to use its strategies and procedures, and an evaluation of their ability to apply such knowledge skillfully in practice. While the assessment of therapists' knowledge has the potential to be completed efficiently on the Web, the assessment of skill has generally involved a labor-intensive process carried out by clinicians, and as such, may not be suitable for assessing training outcome in certain circumstances. OBJECTIVES: The aims of this study were to develop and evaluate a role-play-based measure of skill suitable for assessing training outcome and to compare its performance with a highly scalable Web-based measure of applied knowledge. METHODS: Using enhanced cognitive behavioral therapy (CBT-E) for eating disorders as an exemplar, clinical scenarios for role-play assessment were developed and piloted together with a rating scheme for assessing trainee therapists' performance. These scenarios were evaluated by examining the performance of 93 therapists from different professional backgrounds and at different levels of training in implementing CBT-E. These therapists also completed a previously developed Web-based measure of applied knowledge, and the ability of the Web-based measure to efficiently predict competence on the role-play measure was investigated. RESULTS: The role-play measure assessed performance at implementing a range of CBT-E procedures. The majority of the therapists rated their performance as moderately or closely resembling their usual clinical performance. Trained raters were able to achieve good-to-excellent reliability for averaged competence, with intraclass correlation coefficients ranging from .653 to 909. The measure was also sensitive to change, with scores being significantly higher after training than before as might be expected (mean difference 0.758, P<.001) even when taking account of repeated data (mean difference 0.667, P<.001). The major shortcoming of the role-play measure was that it required considerable time and resources. This shortcoming is inherent in the method. Given this, of most interest for assessing training outcome, scores on the Web-based measure efficiently predicted therapist competence, as judged by the role-play measure (with the Web-based measure having a positive predictive value of 77% and specificity of 78%). CONCLUSIONS: The results of this study suggest that while it was feasible and acceptable to assess performance using the newly developed role-play measure, the highly scalable Web-based measure could be used in certain circumstances as a substitute for the more labor-intensive, and hence, more costly role-play method.

Predictors and moderators of response to enhanced cognitive behaviour therapy and interpersonal psychotherapy for the treatment of eating disorders.

Consistent predictors, and more especially moderators, of response to psychological treatments for eating disorders have not been identified. The present exploratory study examined predictors and moderators of outcome in adult patients who took part in a randomised clinical trial comparing two leading treatments for these disorders, enhanced cognitive behavioural therapy (CBT-E) and interpersonal psychotherapy (IPT). Four potentially important findings emerged. Firstly, patients with a longer duration of disorder were less likely to benefit from either treatment. Second, across the two treatments the presence, at baseline, of higher levels of over-evaluation of the importance of shape predicted a less good treatment outcome. Third DSM-IV diagnosis did not predict treatment outcome. Fourth, with the exception of patients with baseline low self-esteem who achieved a better outcome with CBT-E, it was generally not possible to identify a subgroup of patients who would differentially benefit from one or other treatment.

A transdiagnostic comparison of enhanced cognitive behaviour therapy (CBT-E) and interpersonal psychotherapy in the treatment of eating disorders.

Eating disorders may be viewed from a transdiagnostic perspective and there is evidence supporting a transdiagnostic form of cognitive behaviour therapy (CBT-E). The aim of the present study was to compare CBT-E with interpersonal psychotherapy (IPT), a leading alternative treatment for adults with an eating disorder. One hundred and thirty patients with any form of eating disorder (body mass index >17.5 to <40.0) were randomized to either CBT-E or IPT. Both treatments involved 20 sessions over 20 weeks followed by a 60-week closed follow-up period. Outcome was measured by independent blinded assessors. Twenty-nine participants (22.3%) did not complete treatment or were withdrawn. At post-treatment 65.5% of the CBT-E participants met criteria for remission compared with 33.3% of the IPT participants (p < 0.001). Over follow-up the proportion of participants meeting criteria for remission increased, particularly in the IPT condition, but the CBT-E remission rate remained higher (CBT-E 69.4%, IPT 49.0%; p = 0.028). The response to CBT-E was very similar to that observed in an earlier study. The findings indicate that CBT-E is potent treatment for the majority of outpatients with an eating disorder. IPT remains an alternative to CBT-E, but the response is less pronounced and slower to be expressed. CURRENT CONTROLLED TRIALS: ISRCTN 15562271.

The development of an online measure of therapist competence.

The topic of therapist training has been relatively neglected in the research literature. Similarly, the related issue of the measurement of the outcome of training, especially therapist competence, has been largely overlooked. Data supporting the effectiveness of various methods of clinician training and those providing estimates of the level of competence achieved by clinicians are scarce. Validated scalable methods for the measurement of clinician outcomes such as competence are required to evaluate both existing and new methods of training. This study focuses on the development and testing of an online measure (eMeasure) to assess therapists' applied knowledge of Enhanced Cognitive Behaviour Therapy (CBT-E), a transdiagnostic evidence-supported treatment for the full range of eating disorders. The eMeasure meets the stringent requirements of the Rasch model and has three equivalent versions making it suitable for repeat testing of trainees in outcome studies. Preliminary best cut points to distinguish between those who are competent and those who are not are identified. While the present work focused on CBT-E, the method described may be used to develop and test other measures relating to therapist competence.

Understanding persistence in bulimia nervosa: a 5-year naturalistic study.

Bulimia nervosa shows a marked tendency to persist, suggesting that powerful maintaining mechanisms operate. Using data from a prospective, 5-year, study of the natural course of 102 people with bulimia nervosa, the authors sought to identify predictors of persistence and to test specific hypotheses derived from the cognitive-behavioral theory of the persistence of bulimia nervosa. The results of both sets of analyses were consistent with the theory, with the degree of overevaluation of shape and weight and a history of childhood obesity predicting a persistent course. There was also support for the central prediction of the cognitive-behavioral theory. These findings suggest that the mechanisms specified by the theory influence its longer term natural course.

Enhanced cognitive behaviour therapy for adults with anorexia nervosa: a UK-Italy study.

Anorexia nervosa is difficult to treat and no treatment is supported by robust evidence. As it is uncommon, it has been recommended that new treatments should undergo extensive preliminary testing before being evaluated in randomized controlled trials. The aim of the present study was to establish the immediate and longer-term outcome following "enhanced" cognitive behaviour therapy (CBT-E). Ninety-nine adult patients with marked anorexia nervosa (body mass index ≤ 17.5) were recruited from consecutive referrals to clinics in the UK and Italy. Each was offered 40 sessions of CBT-E over 40 weeks with no concurrent treatment. Sixty-four percent of the patients were able to complete this outpatient treatment and in these patients there was a substantial increase in weight (7.47 kg, SD 4.93) and BMI (2.77, SD 1.81). Eating disorder features also improved markedly. Over the 60-week follow-up period there was little deterioration despite minimal additional treatment. These findings provide strong preliminary support for this use of CBT-E and justify its further evaluation in randomized controlled trials. As CBT-E has already been established as a treatment for bulimia nervosa and eating disorder not otherwise specified, the findings also confirm that CBT-E is transdiagnostic in its scope.

Testing a new cognitive behavioural treatment for obesity: A randomized controlled trial with three-year follow-up.

It is remarkably difficult for people with obesity to maintain a new lower weight following weight loss. The aim of the present study was to examine the immediate and longer-term effects of a new cognitive behavioural treatment that was explicitly designed to minimise this post-treatment weight regain. One hundred and fifty female participants with obesity were randomized to the new treatment, behaviour therapy (the leading alternative psychological treatment) or guided self-help (a minimal intervention). Both of the main treatments resulted in an average weight loss of about ten percent of initial weight whereas weight loss was more modest with guided self-help. The participants were subsequently followed-up for three years post-treatment. The great majority regained almost all the weight that they had lost with the new treatment being no better than the behavioural treatment in preventing weight regain. These findings lend further support to the notion that obesity is resistant to psychological methods of treatment, if anything other than a short-term perspective is taken. It is suggested that it is ethically questionable to claim that psychological treatments for obesity "work" in the absence of data on their longer-term effects.

Transdiagnostic cognitive-behavioral therapy for patients with eating disorders: a two-site trial with 60-week follow-up.

OBJECTIVE: The aim of this study was to compare two cognitive-behavioral treatments for outpatients with eating disorders, one focusing solely on eating disorder features and the other a more complex treatment that also addresses mood intolerance, clinical perfectionism, low self-esteem, or interpersonal difficulties. METHOD: A total of 154 patients who had a DSM-IV eating disorder but were not markedly underweight (body mass index over 17.5), were enrolled in a two-site randomized controlled trial involving 20 weeks of treatment and a 60-week closed period of follow-up. The control condition was an 8-week waiting list period preceding treatment. Outcomes were measured by independent assessors who were blind to treatment condition. RESULTS: Patients in the waiting list control condition exhibited little change in symptom severity, whereas those in the two treatment conditions exhibited substantial and equivalent change, which was well maintained during follow-up. At the 60-week follow-up assessment, 51.3% of the sample had a level of eating disorder features less than one standard deviation above the community mean. Treatment outcome did not depend on eating disorder diagnosis. Patients with marked mood intolerance, clinical perfectionism, low self-esteem, or interpersonal difficulties appeared to respond better to the more complex treatment, with the reverse pattern evident among the remaining patients. CONCLUSIONS: These two transdiagnostic treatments appear to be suitable for the majority of outpatients with an eating disorder. The simpler treatment may best be viewed as the default version, with the more complex treatment reserved for patients with marked additional psychopathology of the type targeted by the treatment.