Mapping the SF-12 to the EuroQol EQ-5D Index in a national US sample. |
| |
Authors: | Peter Franks Erica I Lubetkin Marthe R Gold Daniel J Tancredi Haomiao Jia |
| |
Affiliation: | Department of Family and Community Medicine, Center for Health Services Research in Primary Care, University of California, Davis, Sacramento 95817, USA. pfranks@ucdavis.edu |
| |
Abstract: | BACKGROUND: Preference scores for the Medical Outcomes Study (MOS) SF-12 would enable its use in cost-effectiveness analyses. Previous mapping studies of MOS instruments top reference-based instruments have not examined performance in national samples. PARTICIPANTS: 15,000 adults in the 2000 Medical Expenditure Panel Survey annual survey including the SF-12 and EQ-5D Index. METHODS: Regression of the EQ-5D Index scores onto the physical and mental component summary scores of the SF-12, testing 2nd-4th degree polynomial and spline models, including and excluding sociodemographics. RESULTS: A 2nd degree polynomial model explained 63% of the variance in EQ-5D scores, with robust internal and external validation. More complex mod-els explained minimally additional variance. Compared with EQ-5D valuations, prediction models overestimated the lowest health states (6% of the population). CONCLUSIONS: The mapped SF-12 yields usable preference-scaled scores, with some caution for the lowest health states. |
| |
Keywords: | |
|
|