Introduction:
Patients who present with a principal complaint of disabling fatigue of uncertain cause have received much attention in recent years. Correspondingly there has been an increasing amount of research into this problem. The findings have however often been contradictory. Resolution of these contradictions depends on the ability to compare research studies, but such constructive comparison has rarely been possible. This is largely because research has been carried out by investigators trained in different disciplines, using different criteria to define the condition. Whilst such an eclectic approach is to be welcomed, agreement on case definition, and assessment methods is necessary if progress is to be made.
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Source: Sharpe MC, Archard LC, Banatvala JE, Borysiewicz LK, Clare AW, David A, Edwards RH, Hawton KE, Lambert HP, Lane RJ, et al. A report–chronic fatigue syndrome: guidelines for research. J R Soc Med. 1991 Feb;84(2):118-21. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1293107/