Recruitment and retention in an adolescent anorexia nervosa treatment trial.

To date, few studies have looked at recruitment method in randomized controlled trails (RCTs) for eating disorders, particularly for anorexia nervosa (AN). Halmi and colleagues1 sign a note of caution about treatment trials for adults with AN, specifically by showing the lack of information that has been gathered about how to recruit and retain participants in RCTs. These authors argue that RCTs for AN should not be initiated until more is known about how to recruit and retain this population. Participant recruitment in RCTs is an important yet often overlooked component of study design, perhaps in part due to the low base rate for AN and few published RCTs for this population. Successful recruitment procedures are often based upon anecdotal evidence from previous studies involving similar populations.2 These methods for designing recruitment procedures are not always effective when applied to studies with differing designs and differing populations. Gowers and colleagues3 published an early report on the complexities associated with recruiting participants for a RCT comparing inpatient and outpatient treatments for AN despite a busy inpatient service. These authors encountered a range of both practical and ethical challenges in accomplishing their recruitment goals. In addition, McDermott and her colleagues4 analyzed recruitment rates for three separate RCTs: a study recruiting women partially recovered from AN and two studies recruiting women with current bulimia nervosa (BN). This report finds that recruitment of women partially recovered from AN is a difficult task that requires widespread and intensive recruitment efforts over multiple sites and over a lengthy time-course. By contrast, recruitment of adult women with BN seemed a more achievable goal. In Halmi and colleagues’1 multi-site RCT of adult women with AN, recruitment as well as retention of participants were such significant struggle that the authors decided that they should not analyze their data. Data about participant recruitment in adolescent eating disorders, while limited in scope and scale, are somewhat more promising. Recruitment rates appeared to be reasonable in recently published RCTs.5-7 Retention rates in these adolescent treatment studies were satisfactory with dropout ranging between 10-25%. One of these studies8 detailed their recruitment efforts for adolescents with BN to a treatment trial, which is in accordance with findings that adult BN patients can be recruited consistently and successfully to treatment trials.4 The current report is the second paper in the literature to analyze recruitment rates in an eating disorder treatment trial for adolescents. It draws from our earlier work8 and aims to investigate the feasibility of recruiting and retaining adolescents with AN for an RCT that was conducted at The University of Chicago and Stanford University from April 2005 to March 2009.