The time to trade-off method versus the EQ-5D index to determine health utility in patients with rheumatoid arthritis
https://doi.org/10.14412/1995-4484-2010-829
Abstract
Clinicoeconomic studies require that the health utility index be used to calculate quality-adjusted life years (QALY). Choice of an adequate method for determining health utility for patients with rheumatoid arthritis (RA) makes it necessary to compare various approaches to this assessment.
Objective. To compare health utility values obtained with a time to trade-off (TTO) method and those with the EQ-5D questionnaire. Subjects and methods. A single interview was made in 45 patients with RA (mean RA duration 11.7±6.6 years) with a mean HAQ of 1.22±0.52. Utility was assessed using the direct TTO method, EQ-5D index, and visual analogue scale of general health (VAS-GH); functional disease activity index was assessed according to the Health Assessment Questionnaire (HAQ).
Results. Five (11.2%) patients with RA could not answer a question to calculate TTO. The mean TTO, EQ-5D, and VAS-GH "thermometer" indices were 0.55±0.36, 0.30±0.32, and 0.47±0.23, respectively. Conversion from EQ-5D to utility index yielded the values similar to those with a mean TTO of 0.54±0.29.
The values of the utility index calculated by TTO failed to correlate with those of HAQ and EQ-5D. The disease duration was unrelated to the values of the utility index calculated by any of the methods used. The association of TTO index was found only for VAS-GH "thermometer". Conclusion. EQ-5D index and VAS-GH are the methods of choice in determining health utility for a clinicoeconomic analysis in patients with RA.
Objective. To compare health utility values obtained with a time to trade-off (TTO) method and those with the EQ-5D questionnaire. Subjects and methods. A single interview was made in 45 patients with RA (mean RA duration 11.7±6.6 years) with a mean HAQ of 1.22±0.52. Utility was assessed using the direct TTO method, EQ-5D index, and visual analogue scale of general health (VAS-GH); functional disease activity index was assessed according to the Health Assessment Questionnaire (HAQ).
Results. Five (11.2%) patients with RA could not answer a question to calculate TTO. The mean TTO, EQ-5D, and VAS-GH "thermometer" indices were 0.55±0.36, 0.30±0.32, and 0.47±0.23, respectively. Conversion from EQ-5D to utility index yielded the values similar to those with a mean TTO of 0.54±0.29.
The values of the utility index calculated by TTO failed to correlate with those of HAQ and EQ-5D. The disease duration was unrelated to the values of the utility index calculated by any of the methods used. The association of TTO index was found only for VAS-GH "thermometer". Conclusion. EQ-5D index and VAS-GH are the methods of choice in determining health utility for a clinicoeconomic analysis in patients with RA.
About the Authors
Dmitriy Vladimirovich GoryachevSh F Erdes
Dmitry Vladimirovich Goryachev
Sh F Erdes
References
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Review
For citations:
Goryachev D.V., Erdes Sh.F., Goryachev D.V., Erdes Sh.F. The time to trade-off method versus the EQ-5D index to determine health utility in patients with rheumatoid arthritis. Rheumatology Science and Practice. 2010;48(6):86-89. (In Russ.) https://doi.org/10.14412/1995-4484-2010-829
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