Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A New Name & Diagnostic Criteria World Neurology, The Official Newsletter of the World Federation of Neurology by Maggie L. McNulty is an assistant professor at Rush University Medical Center, Department of Neurological Sciences. In March 2015, a report from the Institute of Medicine (IOM) was published in the Journal of the American Medical Association to redefine the illness known as Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Over the years, clinicians and researchers have developed different diagnostic criteria for ME and CFS; however, the two terms describe conditions with similar symptoms. In the World Health Organization’s “International Classification of Diseases,” 10th Revision, both ME and CFS are coded the same and classified as disorders of the nervous system (ICD G93.3). The term “benign myalgic encephalomyelitis” was first used in the 1950s in London when describing an outbreak in patients who experienced a variety of symptoms, including “malaise, tender lymph nodes, sore throat, pain and signs of encephalomyelitis.” The cause was never found, but it appeared infectious in etiology, and the term “benign myalgic encephalomyelitis” was used to reflect “the absent mortality, the severe muscular pains, the evidence of parenchymal damage to the nervous system and the presumed inflammatory nature of the disorder.” Then in 1970, two psychiatrists reviewed reports of 15 of these outbreaks and concluded that the outbreaks “were psychosocial phenomena” caused by mass hysteria or altered medical perception of the community. MORE: .