Objective: Few randomized, controlled trials have examined the efficacy of treatments for anorexia nervosa. Cognitive behavior therapy and interpersonal psychotherapy are effective in a related disorder, bulimia nervosa. There are theoretical and treatment indications for these therapies in anorexia nervosa.
Method: Fifty-six women with anorexia nervosa diagnosed by using strict and lenient weight criteria were randomly assigned to three treatments. Two were specialized psychotherapies (cognitive behavior therapy and interpersonal psychotherapy), and one was a control treatment combining clinical management and supportive psychotherapy (nonspecific supportive clinical management). Therapy consisted of 20 sessions over a minimum of 20 weeks.
Results: For the total study group (intent-to-treat group), there were significant differences among therapies in the primary global outcome measure. Nonspecific supportive clinical management was superior to interpersonal psychotherapy, while cognitive behavior therapy was intermediate, neither worse than nonspecific supportive clinical management nor better than interpersonal psychotherapy. For the women completing therapy, nonspecific supportive clinical management was superior to the two specialized therapies.
Conclusions: The finding that nonspecific supportive clinical management was superior to more specialized psychotherapies was opposite to the primary hypothesis and challenges assumptions about the effective ingredients of successful treatments for anorexia nervosa.