Abstract
General population preferences for standardized health states are usually obtained for chronic health states. The primary objective of this study was to analyze the feasibility and validity of using time trade-off (TTO) and a visual analog scale (VAS) to elicit preference values for temporary health states (THS=1 year duration, followed by normal health). Subjects were a random sample (n=300) of the general population. 43 health states generated by the EuroQo-5D were valued. The VAS proved slightly more feasible than the TTO. At aggregate level, correlations between VAS and TTO values were high (Spearman r=0.98), and VAS ratings had slightly greater internal consistency and agreement with rank order preferences than the TTO. TTO values were higher than VAS values, and compression of TTO values suggested substantial reluctance to trade. The effect of age on values was reversed between methods, with older respondents scoring higher on the VAS and lower on the TTO, than other age groups. In conclusion, although the VAS proved to be slightly more feasible than the TTO, with slightly greater empirical validity, further research using a wider range of methods to test validity is required before a definitive conclusion on the relative empirical validity of the two valuation techniques can be drawn.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
X. Badia, M. Roset and M. Herdman. “Inconsistent responses in three preference-elicitation methods for health states.” Social Science & Medicine, 49, pp. 943–950, 1999a.
X. Badia, S. Monserrat, M. Roset and M. Herdman. “Feasibility, validity and test-retest reliability of scaling methods for health states: the visual analogue scale and the time trade-off.” Quality of Life Research 8, pp. 303–310, 1999b.
E. B. Bass, E. P. Steinberg, H. A. Pitt, R. I. Griffith, K. D. Lillemoe, G. P. Saba and C. Johns. “Comparison of the rating scale and the standard gamble in measuring patient preferences for outcomes of gallstone disease.” Medical Decision Making 14, pp. 307–314, 1994.
J. Brazier, M. Deverill and C. Green. “A review of the use of health status measures in economic evaluation.” Journal of Health Services Research and Policy 4, pp. 174–184, 1999.
R. Brooks and the EuroQol Group. “EroQol: the current state of play.” Health Policy 37, pp. 53–72, 1996.
J. K. Buckingham, J. Birdsall and J. G. Douglas. “Comparing three versions of the time tradeoff: time for a change?” Medical Decision Making 16, pp. 335–347, 1996.
J. Cook, J. Richardson and A. Street. “A cost-utility analysis of treatment options for gallstone disease: methodological issues and results.” Health Economics 3, pp. 157–168, 1994.
P. Dolan and C. Gudex. “Time preference, duration, and health state valuations.” Health Economics 4, pp. 289–299, 1995.
P. Dolan, C. Gudex, P. Kind and A. Williams. A social tariff for EuroQol: results from a general population survey, Centre for Health Economics, University of York: Discussion paper 138, 1995.
P. Dolan and P. Kind. “Inconsistencies in health state valuations.” Social Science & Medicine 4, pp. 609–615, 1996.
P. Dolan, C. Gudex, P. Kind and A. Williams. “The time trade-off method: results from a general population study.” Health Economics 5, pp. 141–154, 1996a.
P. Dolan, C. Gudex, P. Kind and A. Williams. “Valuing health states: a comparison of methods.” Journal of Health Economics 15, pp. 209–231, 1996b.
D. H. Feeny and G. W. Torrance. “Incorporating utility-based quality-of-life assessment measures in clinical trials.” Medical Care 27, pp. S190–S204, 1989.
F. J. Fowler, P. D. Cleary, M. P. Massagli, J. Weissman and A. Epstein. “The role of reluctance to give up life in the measurement of the values of health states.” Medical Decision Making 15, pp. 195–200, 1995.
D. G. Froberg and R. L. Kane. “Methodology for measuring health-state preferences—II: scaling methods.” Journal of Clinical Epidemiology 42, pp. 459–471, 1989.
R. R. Gold, J. E. Siegel, L. B. Russell and M. C. Weinstein. Cost-effectiveness in Health and Medicine, Oxford: Oxford University Press.
C. Gudex, P. Dolan, P. Kind and A. Williams. “Health state valuations from the general public using the visual analogue scale.” Quality of Life Research 5, pp. 521–531, 1996.
S. J. T. Jansen, A. M. Stiggelbout, P. P. Wakker, T. P. M. Vliet Vlieland, J. H. Leer, M. A. Nooy and J. Kievit. “Patients' utilities for cancer treatments: a study of the chained procedure for the standard gamble and time tradeoff.” Medical Decision Making 18, pp. 391–399, 1998.
J. A. Johnson, S. J. Coons, A. Ergo and G. Szava-Kovats. “Valuations of EuroQOL (EQ-5D) health states in an adult US sample.” PharmacoEconomics 4, pp. 421–433, 1996.
K. Johnston, J. Brown, K. Gerard, M. O'Hanlon and A. Morton. “Valuing temporary and chronic health states associated with breast screening.” Social Science & Medicine 2, pp. 213–222, 1998.
R. M. Kaplan, J. W. Bush and C. C. Berry. “The reliability, stability and generalizability of a health status index,” In Proceedings, Social Status Section, American Statistical Association, 704–709, 1978.
H. A. Llewellyn-Thomas, H. J. Sutherland and E. C. Thiel. “Do patients' evaluations of a future health state change when they actually enter that state?” Medical Care 31, pp. 1002–1012, 1993.
H. Llewellyn-Thomas, H. J. Sutherland, R. Tibshirani, A. Ciampi, J. E. Till and N. F. Boyd. “Describing health states: methodologic issues in obtaining values for health states.” Medical Care 6, pp. 543–552, 1984.
G. Loomes and L. McKenzie. “The use of QALYs in health care decision making.” Social Science & Medicine 28, pp. 299–308, 1989.
E. Pfeiffer. “A short portable mental status questionnaire for the assessment of organic brain deficit in elderly patients.” Journal of the American Geriatrics Society 10, pp. 433–441, 1975.
A. Robinson, P. Dolan and A. Williams. “Valuing health status using VAS and TTO: what lies behind the numbers?” Social Science & Medicine 8, pp. 1289–1297, 1997.
D. L. Sackett and G. W. Torrance. “The utility of different health states as perceived by the general public.” Journal of Chronic Diseases 31, pp. 697–704, 1978.
S. S. Stevens. “A metric for the social consensus.” Science 151, p. 530, 1966.
A. M. Stiggelbout, G. M. Kiebert, J. Kievit, J. W. Leer, G. Stoter and J. C. de Haes. “Utility assessment in cancer patients: adjustment of time tradeoff scores for the utility of life years and comparison with standard gamble scores.” Medical Decision Making 1, pp. 82–90, 1994.
G. W. Torrance. “Social preferences for health states: an empirical evaluation of three measurement techniques.” Socio-Economic and Planning Science 10, pp. 129–136, 1976.
G. W. Torrance. “Measurement of health state utilities for economic appraisal: a review.” Journal of Health Economics 5, pp. 1–30, 1986.
G. W. Torrance. “Utility approach to measuring health-related quality of life.” Journal of Chronic Diseases 6, pp. 593–600, 1987.
G. W. Torrance, D. H. Feeny, W. J. Furlong, R. D. Barr, Y. Zhang and Q. Wang. “Multi-attribute utility function for a comprchensive health status classification system: Health Utilities Index Mark II.” Medical Care 7, pp. 702–722, 1996.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Badia, X., Herdman, M., Roset Dipstat, M. et al. Feasibility and Validity of the VAS and TTO for Eliciting General Population Values for Temporary Health States: A Comparative Study. Health Services & Outcomes Research Methodology 2, 51–65 (2001). https://doi.org/10.1023/A:1011480201653
Issue Date:
DOI: https://doi.org/10.1023/A:1011480201653