Predictors of dropout in face‐to‐face and internet‐based cognitive‐behavioral therapy for bulimia nervosa in a randomized controlled trial

Abstract

Objective We sought to identify predictors and moderators of failure to engage (i.e., pretreatment attrition) and dropout in both Internet-based and traditional face-to-face cognitive-behavioral therapy (CBT) for bulimia nervosa. We also sought to determine if Internet-based treatment reduced failure to engage and dropout. Method Participants (N = 191, 98% female) were randomized to Internet-based CBT (CBT4BN) or traditional face-to-face group CBT (CBTF2F). Sociodemographics, clinical history, eating disorder severity, comorbid psychopathology, health status and quality of life, personality and temperament, and treatment-related factors were investigated as predictors. Results Failure to engage was associated with lower perceived treatment credibility and expectancy (odds ratio [OR] = 0.91, 95% CI: 0.82, 0.97) and body mass index (BMI) (OR = 1.10; 95% CI: 1.03, 1.18). Dropout was predicted by not having a college degree (hazard ratio [HR] = 0.55; 95% CI: 0.37, 0.81), novelty-seeking (HR = 1.02; 95% CI: 1.01, 1.03), previous CBT experience (HR = 1.77; 95% CI: 1.16, 2.71), and randomization to the individual's nonpreferred treatment format (HR = 1.95, 95% CI: 1.28, 2.96). Discussion Those most at risk of failure to engage had a higher BMI and perceived treatment as less credible and less likely to succeed. Dropout was associated with less education, higher novelty-seeking, previous CBT experience, and a mismatch between preferred and assigned treatment. Contrary to expectations, Internet-based CBT did not reduce failure to engage or dropout.

Adherence as a predictor of dropout in Internet‐based guided self‐help for adults with binge‐eating disorder and overweight or obesity

“…Predictors of dropout within GSH‐I are virtually unknown, except that greater shape concerns at baseline were associated with higher dropout in patients with BED (Carrard et al, ). Evidence from Internet‐based group CBT in BN indicated that dropout was predicted by treatment motivation (Watson et al, ). In GSH‐I for patients with eating disorder symptoms, improvements of the motivational state of change were predicted by high levels of patients' adherence (Leung, Ma, & Russell, ), operationalized as the frequency of utilizing specific treatment components (Donkin et al, ; Fuhr et al, ).…”

The association between program credibility, expectancy, and acceptability with baseline pathology and outcome for a body acceptance prevention program

“…Within the eating disorders literature, Watson et al. () also found that lower credibility scores predicted first session attendance of cognitive‐behavioral therapy (CBT) in a sample of individuals with bulimia nervosa; interestingly, these scores were not related to symptom severity or treatment outcomes. Research investigating treatment credibility before and after exposure to treatment has found that credibility scores after exposure are more predictive of future outcomes (Mooney et al., ).…”

“…Examining these nonspecific intervention factors may elucidate risk factors associated with lower (or better) program response. For example, treatment credibility, which refers to an individual's belief about how convincing and logical a treatment seems (Kazdin & Wilcoson, 1976), has been associated with drop-out and poorer treatment outcomes in psychother- Watson et al (2016) also found that lower credibility scores predicted first session attendance of cognitive-behavioral therapy (CBT) in a sample of individuals with bulimia nervosa; interestingly, these scores were not related to symptom severity or treatment outcomes. Research investigating treatment credibility before and after exposure to treatment has found that credibility scores after exposure are more predictive of future outcomes (Mooney et al, 2014).…”

Ross D. Crosby: Scholar, teacher, mentor, and friend. Introducing a virtual issue honoring the contributions of Ross D. Crosby to the field of eating disorders

“…The large subset of patients who continue to report eating disorder symptoms is a stark reminder of the disorder's severity and the urgent need to improve outcomes. It is, therefore, noteworthy that studies focused on treatment development and exploration of predictors, moderators and mediators of treatment outcome have been another focus of Dr. Crosby's collaborative work in the field and included here are five such studies (Graves et al, ; Haynos et al, ; Peterson et al, ; Tanofsky‐Kraff et al, ; Watson et al, ).…”

“…Predictors of failure to engage were lower perceived treatment credibility, lower expectancy to succeed in treatment, and higher body mass index (BMI). Among patients who initiated treatment, dropout was significantly associated with lower educational attainment, higher novelty seeking, previous CBT experience, and a mismatch between preferred and assigned treatment (Watson et al, ). In another treatment study included in this issue, the indirect effects of integrative cognitive‐affective therapy (ICAT‐BN) and cognitive‐behavioral therapy‐enhanced (CBT‐E) on BN treatment outcome were examined through three hypothesized maintenance variables: emotion regulation, self‐directed behavior, and self‐discrepancy.…”