ME/CFS: A Clinical Working Case Definition and Guidelines for Medical Practitioners (2005)

The Consensus Document (popularly known as the "Canadian Guidelines") was compiled under Terms of Reference devised by Health Canada and drawn up by an international team of ME/CFS practitioners and researchers from Canada, US and Belgium with the combined experience of treating over 20,000 people with ME/CFS.

The Clinical Case Definition recognises common clusters of symptoms.  To be diagnosed with ME/CFS, seven specific criteria have to be met. A patient needs to satisfy criteria for:

• Fatigue;
• Post-exertional malaise and/or fatigue;
• Sleep dysfunction;
• Pain;
• Experience two or more listed neurological/cognitive manifestations;
• Have one or more symptoms from two of the categories of autonomic, neuroendocrine and immune manifestations;
• The illness needs to have persisted for at least six months (three months for children).

Other illnesses also need to be excluded.

For more information, see page 2 of the Overview of the Canadian Guidelines for the Canadian Clinical Working Case Definition.

The Adelaide Forum (2005), an informal meeting of eminent international and Australian ME/CFS researchers and clinicians, agreed to unanimously embrace the Canadian Case Definition of ME/CFS with a strong recommendation that it be taken up by the ME/CFS organisations in Australia.

ME/CFS Australia has endorsed the Canadian Consensus Document and promotes the use of the Canadian Clinical Case Definition for the diagnosis of ME/CFS.

Pediatric Case Definition of ME/CFS (2006)

A case definition (2006) has been written specifically for children and adolescents. The definition has adopted the Canadian ME/CFS criteria of symptom clusters and included some elements of the Fukuda (1994) definition of CFS (and the 2003 suggested modifications). Access the Pediatric Case Definition here.

Fukuda Diagnostic Criteria for Chronic Fatigue Syndrome (1994)

These guidelines lack sensitivity and specificity and are not recommended for diagnosis. For more information on the Fukuda Diagnostic Criteria, click here.