Definitions of myalgic encephalomyelitis and chronic fatigue syndrome

Over the course of almost three decades, many definitions or criteria have been developed to diagnose either ME, CFS or ME/CFS and SEID.

ME

 * 1986 Ramsay definition
 * 2007 Nightingale definition
 * 2011 International Consensus Criteria
 * 2014 London criteria

CFS

 * 1988 CDC case definition ("Holmes criteria")
 * 1991 Oxford criteria
 * 1994 CDC case definition ("Fukuda criteria")
 * 2005 CDC case definition ("Empirical definition")

Combined (ME/CFS)

 * 2003 Canadian Consensus Criteria
 * 2007 NICE guidelines

SEID

 * 2015 IOM diagnostic criteria (SEID)

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Comparative Graphs

 * Case Definition Comparison - Graph 1