Most patients have difficulty in rating themselves on visual analogue scales

Editor—The recent finding that patients' self assessments on a visual analogue scale did not correlate with other measures of disability in multiple sclerosis comes as no surprise to us.1 Visual analogue scales, which are used widely in studies of health status and quality of life, ask patients to rate themselves on a calibrated scale, usually from 0 to 100. The language of the end points or anchors of the scale varies, but, usually, 100 represents best possible health or quality of life and 0 represents the worst possible health or quality of life. In our experience, of several hundred interviews with patients with neurological disorders (epilepsy, Parkinson's disease, Gilles …