The concurrent occurrence of four or more of the following symptoms:
- substantial impairment in short-term memory or concentration;
- sore throat;
- tender lymph nodes;
- muscle pain;
- multi-joint pain without swelling or redness;
- headaches of a new type, pattern, or severity;
- unrefreshing sleep; and
- post-exertional malaise lasting more than 24 hours.
These symptoms must have persisted or recurred during 6 or more consecutive months of illness and must not have predated the fatigue.
PDF By: IACFSME
Criteria, Exclusions and Severity.
- Post-exertional malaise (PEM) is not mandatory. (Most US researchers do use PEM option.)
- Doctors and researchers not using PEM option have misdiagnosed Chronic Fatigue (CF) patients with Chronic Fatigue Syndrome (CFS).
- In research, if PEM option is not used the study is not considered by patients and many researchers to be a true CFS study; it is considered to be a (CF) study. Or both CFS and CF patients are in a CFS study as some patients have PEM and other patients do not making the study severely flawed and useless to either CFS or CF research.
- It is not easy to use on a clinical level as it was created for research. It can take several specialists and years to diagnose a patient.
- Dual diagnosis is not always possible and this is not useful in a clinical setting. (i.e., AIDS + CFS or MS + CFS.)
- Leads to confusion over Chronic Fatigue (a symptom of many illness, depression, diseases, medications) and Chronic Fatigue Syndrome (a grossly misnamed disease.)
- Fukuda criteria
- CDC criteria
- 2004, Comparing the Fukuda et al. Criteria and the Canadian Case Definition for Chronic Fatigue Syndrome. Leonard Jason et al.
- 2003, Identification of ambiguities in the 1994 chronic fatigue syndrome research case definition and recommendations for resolution, by Reeves, et al.
- 2001, A Comparison of the 1988 and 1994 Diagnostic Criteria for Chronic Fatigue Syndrome. Leonard Jason et al.