Abstract
It has been a common occurrence that children with chronic, unexplained fatigue receive no specific diagnosis because of difficulties posed by the 1988 research criteria for chronic fatigue syndrome (CFS). The lack of a specific diagnosis creates medical uncertainty and may lead to increased psychosocial and educational disruption. With the recent publication of new research criteria these problems may be improved as the new criteria are less restrictive. In the process of developing new research criteria, data was collected for children who presented for evaluation of chronic unexplained fatigue over a two year period. Diagnosis of CFS was based upon the 1988 CDC criteria or clinical criteria based upon activity limitation and the associated symptom complex. Comparison of these two groups showed differences in symptom severity and degree of activity limitation, while demographics, psychosocial variables, and symptom pattern were similar. These results would suggest that chronic fatigue syndrome exists in a continuum of severity and that definition based solely upon severity of fatigue is arbitrary. While severe and debilitating fatigue should remain the basis of any research definition, clinical criteria based upon the symptom pattern of CFS may improve long term management by providing a working clinical diagnosis.