A BRIEF MENTAL FATIGUE QUESTIONNAIRE

A brief mental fatigue questionnaire was administered to normal subjec ts and muscle-diseased, Chronic Fatigue Syndrome (CFS), recovered CFS and depressed patients. The questionnaire was found to have excellent internal consistency and discriminated effectively between CFS and dep ressed patients on the one hand and recovered CFS, normal and muscle-d iseased patients on the other. However, the scale failed to discrimina te between CFS and depressed subjects, who were found to experience qu alitatively and quantitatively similar mental fatigue symptoms.