1. A Statistics Canada Community Health Survey
   Statistics Canada Community Health Surveys[i] indicate that the prevalence of adults diagnosed with Chronic Fatigue Syndrome in Canada  was:
        2001  - 199,746
        2003  -  341,126
        2005 - 1.3%  or 390,000 (Community Health Survey - Statistics Canada)
   

2. This increase of over 58% in the two-year period between 2001 and 2003 suggests that
   

   1. there is an alarming increase in this chronic and often severely debilitating illness,
   2. or some physicians lacked sufficient knowledge about the illness to make an accurate diagnosis,
   3. or physicians are making inappropriate diagnoses.
      

Reeves Criteria
A study using the Reeves criteria (2005) suggest that the  prevalence rate runs as high as 2.5%.  However, the Reeves criteria for CFS/ME includes many patients that do not have ME/CFS.  It is suggested that only approximately 20% or less of the people diagnosed using the Reeves criteria actually have ME/CFS.  Some criteria are not specific to ME/CFS and is probably selecting more patients with depression than those with ME/CFS.  Due to the inability of this definition to select ME/CFS patients, we will not include consider their prevalence figures.

FMS

1. Statistics Canada Community Health Survey suggest that 1.5% (495,000) of the Canadian population are afflicted with FMS. 
   
2. Many international prevalence studies consistently found that FMS is more prevalent that ME/CFS and indicate that FMS afficts between 2 and 10% (660,000 - 3,300,000) of the adult population. 
   
   There are two studies done by Canadian researchers, which obtained very similar results, and are in line with international studies.
3. The 1999 study by White et al.[ii] suggests that 3.3% or 825,000 of non-institutionalized Canadians have FMS.
4. These figures are supported by an earlier study[iii]  by Dr. Elizabeth Badly, who did a study city by city and province by province, that indicated that 822,000 Canadians had been diagnosed with FMS in 1994.  This is by far the most in-depth study done on FMS prevalence.
5. The prevalence figures in the White and Badly studies are extremely close and are in line with international studies.  Based on these studies, it is conservatively safe to say over 1,000,000 Canadians are afflicted with FMS.
   

Summary

On the conservative side, it is probably safe to say that approximately 1,250,000 adult Canadians have ME/CFS or FMS.

Problem with Patient Selection Criteria

[ii] White KP, Speechley M, Harth M, Ostbye T. The London fibromyalgia epidemiology study: the prevalence of fibromyalgia syndrome in London, Ontario. Journal of Rheumatology 26(7):15700-1576, 1999.

[iii] Badly E. Prevalence of Arthritis in Canada. Arthritis Community Research and Evaluation Unit, Wellesley Hospital, Toronto, Ontario. June 1994.