This presentation is part of: Poster Session - Utility Theory; Health Economics; Patient & Physician Preferences; Simulation; Technology Assessment
THE GAP EFFECT: DISCONTINUITIES OF PREFERENCES AROUND DEAD
Peep F. M. Stalmeier, PhD1, Jan J.V. Busschbach, PhD2, Leida L Lamers, PhD3, and Paul F. M. Krabbe, PhD1. (1) University MC Nijmegen, Department of Medical Technology Assessment, Nijmegen, Netherlands, (2) Erasmus Medical Center, Department of Medical Psychology, Rotterdam, Netherlands, (3) Erasmus MC Rotterdam, Medical Technology Assessment, Rotterdam, Netherlands
Background: The assessment of negative values for health states considered to be worse than dead is a controversial issue. Objective: To investigate how health states are valued when they are close to dead. Methods: A secondary analysis of the EuroQol EQ-5D data of the Measurement of Valuation and Health (MVH) study was made. Visual Analog Scale (VAS) and Time Trade-Off (TTO) values for 43 health states were given by 3395 respondents. For each respondent, states were rank ordered by their VAS and TTO scores. For these rank ordered states, better than dead, equal to dead, and worse than dead preferences were defined. Differences between the valuations of adjacent rank ordered states for the VAS and the positive and negative TTO scores were calculated. Results: Complete data were obtained in 2997 respondents. The differences between the ordered VAS scores decreased gradually as the health states deteriorated. In contrast, significant gaps around dead were found for the positive as well as the negative TTO scores. Discussion: These results are interpreted in light of a descriptive QALY model. This model was expanded to include utilities worse than dead. The VAS task does not pick up that bad states become intolerable, i.e. worse than dead, when they last too long, but the TTO task does. The current QALY model seems to lack descriptive validity for states valued worse than dead.
