They say "it's accurate," but this is a total crock. For one thing, they have clearly stated that the Emperical definition is a research definition, and not meant for clinical use. If it's not meant for clinical use, why do they put it into their clinical tool kit. Why are they not telling clinicians that they are giving them an unsuitable definition. The answer is they have no integrity. And how do they back up their claim about GET. They do not cite any studies that use their definition of CFS. What they do is cite Oxford criteria studies, which have definitions that disagree with the CDC definition, the Canadian definition, and the International definition. .