Concept of benign myalgic encephalomyelitis.

The reports of the 15 recorded outbreaks of benign myalgic encephalomyelitis have been reviewed and in one instance the original clinical data studied. We believe that a lot of these epidemics were psychosocial phenomena caused by one of two mechanisms, either mass hysteria on the part of the patients or altered medical perception of the community. We suggest that the name "myalgia nervosa" should be used for any future cases of functional disorder which present the same clinical picture.