Long-term outcome research in anorexia nervosa: The problem of patient selection and follow-up duration

The majority of follow-up studies of anorexia nervosa patients appears to have little reliability if judged according to current research standards. Our own long-term outcome investigation of 128 hospitalized anorexia nervosa patients revealed some problems that seem to be easily overlooked in the literature. First, we were faced with a high rate of failure in tracing patients at follow-up. Second, our consecutive series of patients showed great differences in time span between first presentation and follow-up assessment. The analysis of both issues—patient selection and follow-up duration—brings out some important difficulties with regard to the interpretation of the results.