The literature was studied on the existence of differences in valuation for
hypothetical and actual health states between patients and other-rater gro
ups. It was found that nine different study designs have been used to study
this question and two of these designs were applied in a study involving d
ialysis patients and other rater groups. In the first study, both dialysis
patients and students had to value hypothetical health states with Standard
Gamble (SG) and Time Trade Off (TTO). Patients assigned higher values to h
ypothetical health states than students did. In the second study, dialysis
patients who were being treated with four different dialysis modalities wer
e asked to value their own health state with SG, TTO and a visual analogue
scale (EQ(VAS)), and to describe their health state on the EQ-5D(profile).
Several EQ-5D(index) values (health index values derived from general popul
ation samples) were calculated for the four dialysis treatment groups, base
d on the EQ-5D(profile). These health indexes could discriminate between tr
eatment groups, according to clinical impressions. Treatment groups could n
ot be differentiated based on patients' valuations of own health state. The
results suggest that general population samples, using EQ-5D(index) values
, may be more able to discriminate between patient groups than the patients
themselves are. The implications of this finding for valuation research an
d policy-making are discussed. Copyright (C) 2000 John Wiley & Sons, Ltd.