Use of the Canadian criteria to diagnose CFS, British Medical Journal, 18 July 2011: http://www.meassociation.org.uk/?p=7156
Fiona Godlee suggests that adoption of the Canadian criteria to diagnose chronic fatigue syndrome (CFS) is a reasonable request (1). It may be reasonable, but is probably not practicable.
These criteria require the assessment of some 65 discrete symptoms and 14 comorbid conditions, before even considering exclusionary conditions (2); a significant burden on both patients and doctors. More worrying is that “symptoms”, such as ataxia, “palpitations with cardiac arrhythmias”, and “loss of thermostatic stability” count towards the diagnosis, rather than suggesting alternative diagnoses.
All criteria used to diagnose CFS/ME require disabling fatigue lasting between 4 and 6 months; a varying number of symptoms and the exclusion of other illnesses that cause fatigue. There is no evidence that different diagnostic criteria diagnose a different condition (3).
There has been a recent attempt to improve the “vaguely worded” Canadian criteria (4), incorporating elements of more orthodox research criteria (5). But these revised criteria still require assessment of too many symptoms of dubious validity.
The one advantage of the Canadian criteria over alternative diagnostic criteria is that they require what many would regard as the characteristic feature of CFS, post-exertional malaise (6). This is something that may need incorporating in future definitions to help differentiate CFS from more general fatigue.
BMJ Rapid response - link will take you to original Godlee article: "Ending the Stalemate":
http://www.bmj.com/content/342/bmj.d3956/reply#bmj_el_266989