Chronic fatigue syndrome definition

Definitions, Guidelines, and Summaries
In 1938, Gilliam reported an epidemic of the illness giving a detailed description that added up to a twenty-point definition. His report came to be recognized as the first useful description of ME, but official acknowledgment of its existence was delayed by concerned US authorities for four years.

Competing definitions, guidelines, and summary descriptions have accrued since then. Among them, some of the most notable are


 * The Ramsay definition (1986)


 * The Holmes et al (1988) scoring system, sometimes called "CDC 1988"


 * The Oxford criteria (1991)


 * The "Fukada" CDC definition (1994), or "CDC 1994"


 * The Carruthers et al (2003) Canadian Case definition for ME/CFS


 * The NICE (UK) 2007 criteria, a multidisciplinary clinical practice guideline published in 2007 by the UK's National Institute for Health and Clinical Excellence (NICE)

Case definitions in CFS have largely been established to define patients for research study purposes, and have certain limitations when used for general practitioner purposes. Several studies have found that using different case definitions ( eg broad vs conservative ) has major influence on the types of patients selected and have also supported the distinction between specific subgroups of CFS to be identified and/or for the case definition to be further clarified with emphasis on using empirical studies: An international CFS study group for the CDC found in 2003 that ambiguities in the CDC 1994 CFS research case definition contribute to inconsistent case identification.

At this time, there is no accepted conclusive test or series of tests for ME/CFS. According to the CDC, the main purpose of performing diagnostic tests of any sort at this point in time, is to rule out other causes for fatigue and other symptoms of CFS. A review published in 2006 found that the accurate diagnosis of CFS is low

Clinical practice guidelines, with the aim of improving diagnosis, several countries have now produced these, which are generally based on case descriptions but these documents have the aim of guiding decisions and criteria regarding diagnosis, management, and treatment. Modern medical guidelines are based on an examination of current evidence within the paradigm of evidence-based medicine and they usually include summarized consensus statements. Guidelines are usually produced at national or international levels by medical associations or governmental bodies.