Rationale: When comparing patients' pain ratings with the health care professional's conception of pain assessed by Visual Analogue Scales (VAS) ratings, statistical problems arise.
Method and result: In this data simulation study we have shown that the tendency for health care professionals to underestimate severe pain compared with mild pain is probably not attributed to difficulties in judging severe pain more often than mild but the result of professionals having a different and often narrower distribution of their ratings compared with patients.