Background: Health utilities (HU) assign preference weights to specific health states and are required for cost effectiveness analyses. Existing HU for stroke inadequately reflect the spectrum of post-stroke disability. Using international stroke trial data, we calculated HU stratified by disability to improve precision in future cost-effectiveness analyses.Materials and methods: We used European Quality of Life Score (EQ-5D-3L) data from the Virtual International Stroke Trials Archive (VISTA) to calculate HU, stratified by modified Rankin Scale scores (mRS) at 3 months. We appliedpublished value sets to generate HU, and validated these using ordinary least squares regression, adjusting for age and baseline National Institutes of Health Stroke Scale (NIHSS) scores.Results: We included 3858 patients with acute ischemic stroke in our analysis (mean age: 67.512.5, baseline NIHSS: 125). We derived HU using value sets from 13 countries and observed significant international variation in HU distributions (Wilcoxon signed-rank test p<0.0001, compared with UK values). For mRS¼0, mean HU ranged from 0.88 to 0.95; for mRS¼5, mean HU ranged from 0.48 to 0.22. OLS regression generated comparable HU (for mRS¼0, HU ranged from 0.9 to 0.95; for mRS¼5, HU ranged from 0.33 to 0.15). Patients’ mRS scores at3 months accounted for 65–71% of variation in the generated HU.Conclusion: We have generated HU stratified by dependency level, using a common trial endpoint, and describing expected variability when applying diverse value sets to an international population. These will improve future cost effectiveness analyses. However, care should be taken to select appropriate value sets.
- preference weights
Ali, M., MacIsaac, R., Quinn, T. J., Bath, P. M., Veenstra, D. L., Xu, Y., Brady, M. C., Patel, A., & Lees, K. R. (2017). Dependency and health utilities in stroke: data to inform cost-effectiveness analyses. European Stroke Journal , 2(1), 70-76. https://doi.org/10.1177/2396987316683780