Binge-eating disorder (BED) is defined by recurrent binge eating (eating unusually large quantities of food accompanied by feelings of loss of control), marked distress, and the absence of inappropriate weight compensatory behaviors that characterize bulimia nervosa. The disorder is prevalent and is associated with obesity (Hudson, Hiripi, Pope, & Kessler, 2007), elevated risk for medical (Johnson, Spitzer, & Williams, 2001), and psychiatric co-morbidity (Grilo, White, & Masheb, 2009). BED has diagnostic validity, is distinct from other eating disorders (Grilo, Crosby, et al., 2009) and obesity (Grilo et al., 2008), and is a formal eating disorder in the DSM-5 ( American Psychiatric Association, 2013).
Research has found that certain psychological treatments are effective for BED (Wilson, Grilo, & Vitousek, 2007). Of these, cognitive-behavioral therapy (CBT), is the most widely studied and best-established treatment for BED (National Institute for Clinical Excellence (NICE), 2004 and Wilson et al., 2007). CBT has demonstrated “treatment specificity” (Grilo, Masheb, & Wilson, 2005) and durable outcomes for 12-months (Grilo, Crosby, Wilson, & Masheb, 2012; Grilo, Masheb, Wilson, Gueorguieva, & White, 2011) through 48-months (Hilbert, Bishop, Stein, & Wilfley, 2012) following treatment in specialist clinics.
Unfortunately, despite the existence of empirically-supported CBT methods for BED and other eating disorders (Wilson et al., 2007), only a small number of individuals with eating/weight concerns receive mental health services (Marques et al., 2011), and even fewer receive treatments with documented effectiveness (Hart et al., 2011 and Wilson and Zandberg, 2012). There is a shortage of clinicians with specialized training in CBT (Kazdin and Blase, 2011 and Shafran et al., 2009) in general, and this is particularly the case for eating disorders (Hart et al., 2011). Furthermore, research suggests that even clinicians who describe themselves as delivering CBT-based interventions for disordered eating do not follow most key aspects of empirically-supported CBT (Tobin et al., 2007 and Waller et al., 2012). Thus, one of the most pressing research needs facing the eating disorder field is for research on greater dissemination of effective treatment methods (Shafran et al., 2009 and Wilson and Zandberg, 2012).
In an effort to address the need for dissemination of effective interventions, initial treatment studies with various forms of guided self-help and “pure” self-help CBT have shown promise for addressing BED (National Institute for Clinical Excellence (NICE), 2004, Sysko and Walsh, 2008 and Wilson and Zandberg, 2012). Controlled trials have found that “guided” self-help CBT – that is, with some form of facilitation or guidance by a clinician – has efficacy for BED across diverse clinical and community settings (see critical reviews by Sysko and Walsh, 2008 and Wilson and Zandberg, 2012), with one controlled trial documenting “treatment-specificity” for guided self-help CBT versus guided self-help behavioral weight loss (Grilo & Masheb, 2005). Much less research, however, has examined “pure” self-help CBT - that is, self-help that is purely self-directed and without guidance from a clinician. While inspection of findings across studies suggests that pure self-help tends to be less beneficial than guided self-help (Sysko and Walsh, 2008 and Wilson and Zandberg, 2012), only three studies that have directly tested pure self-help CBT for BED against no-self-help (i.e., wait-list) and these have yielded mixed results. Carter and Fairburn (1998) and Peterson et al. (1998) found that pure self-help CBT was superior to wait-list control in trials performed with a community-based sample and in a specialty clinic, respectively. More recently, however, in a larger trial Peterson, Mitchell, Crow, Crosby, and Wonderlich (2009) found that self-help CBT was not superior to wait-list control in a trial performed at a specialty clinic. Thus, further research is needed on the effectiveness of self-help CBT methods for BED across diverse settings (Wilson & Zandberg, 2012).
The existing treatment literature for BED is based mostly on trials performed in specialist research clinics and findings may not generalize adequately due to potential confounds associated with various clinic biases (Grilo, Lozano, & Masheb, 2005) or to more diverse patient groups comprising different ethnic/racial minorities (Franko, Thompson-Brenner, Thompson, et al, 2012). For example, African-American and Hispanic groups are vastly under-represented in the existing treatment literature for BED (Franko et al., 2012) with participation rates that are much lower than expected based on prevalence rates reported in epidemiological studies (Alegria et al., 2007 and Marques et al., 2011). The three RCTs testing pure self-help CBT for BED consisted of 97% (Carter & Fairburn, 1998), 96.1% (Peterson et al., 1998), and 96.5% (Peterson et al., 2009) white participants. Furthermore, studies have found that minority groups with eating disorders have lower mental health utilization rates than whites and receive most of their health care from generalist or primary care settings rather than specialists (Marques et al., 2011).
The present study was designed to provide new information about the effectiveness of (pure) self-help CBT – initiated by generalist clinicians – as a potential first-step intervention method in primary care. BED is associated with increased health-care service utilization in general primary care settings (Johnson et al., 2001) but binge eating problems are infrequently identified by general healthcare providers (Mond, Myers, Crosby, Hay, & Mitchell, 2010). In addition to gaining a better understanding of the effectiveness of pure self-help CBT and extending research into generalist medical settings, there is a pressing need for treatment research to include more diverse patient groups (Franko et al., 2012). Thus, this RCT was designed to provide information about the effectiveness of self-help CBT amongst a diverse sample of patients with BED in a highly relevant generalist medical setting.