A review of the definitions of outcome used in the treatment of bulimia nervosa

There are many terms used to describe treatment outcome for bulimia nervosa. However, the way such terms are conceptualised across various studies differs dramatically, making comparison of outcomes difficult. A consensus working definition of pivotal terms such as remission and recovery is important if treatments are to be adequately evaluated and clinical meaning derived for individuals with bulimia nervosa (BN). The central aim of the current review was to identify different definitions of remission and recovery and their utility in terms of client outcome after treatment for BN. Seventy one unique published treatment studies were identified that used 82 different outcome measures, of which 63 (77%) used behavioural outcomes only, with the most commonly used outcome (n = 7 studies) being an abstinence of bingeing and vomiting for a 4 week period. The problems with the definitions of outcomes used to date are explored, and the implications of research in anorexia nervosa for forming consensus definitions of remission and recovery for BN will be examined. In addition, the review highlights the importance of considering the relationship between quality of life and outcome in assessing the “goodness of fit” of a definition of outcome.

► We review 71 published treatment studies for bulimia nervosa and related disorders.
► Across these studies 82 different primary outcome measures were used.
► 77% of the studies included a measure of behavioural functioning only.
► Only 33% of the behavioural definitions of outcome used more than once.
► Comparison of outcomes across studies is hard to derive meaningfully; and uniform definitions of remission and recovery are suggested.