Fukuda criteria

The Fukuda criteria (or CDC criteria) for chronic fatigue syndrome was published in 1994.

Definition
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.