Should the Preference-Based Index Set of Values be Country or Disease Specific? An Analysis Using Data From Women With Symptoms of Overactive Bladder

Objectives: Overactive bladder (OAB) and urinary incontinence (UI) are common conditions among women. We aimed to verify the difference between the preference-based index extracted from short-form six-dimension version one (SF-6Dv1) in women with OAB using different country-specific value sets, translate and cross-culturally adapt the King's Health Questionnaire Five Dimension (KHQ-5D) into Brazilian Portuguese, and examine the association between preference-based index obtained by the SF-6Dv1 and KHQ-5D. Methods: This cross-sectional study included 387 women with OAB, divided into groups with and without UI. The participants answered the sociodemographic questionnaire, KHQ, KHQ-5D, and SF-6Dv1. A two-way mixed analysis of variance, with post hoc to multiple comparisons were applied and a Spearman's test was applied to verify the correlation between the preference-based index of SF-6Dv1 and KHQ-5D.Results: The main analysis showed a statistically significant interaction between the presence of UI and the value set obtained from the different countries (P = .005, Cohen's d = 0.02). The post hoc analyses showed that there was a statistically significant main effect of the value sets obtained from different countries (P ,.001, d = 0.63) andin the presence of UI (P = .012, d = 0.02). The correlations between the preference-based index obtained from different countries using the SF-6Dv1 and KHQ-5D were significant. Conclusions: Differences were observed between the preference-based index obtained in different countries and presence of UI, although positive and significant results were observed in the correlation between preference-based index from different countries. The correlation between general and specifics preference-based index was small; the SF-6Dv1 could be used in cost-utility studies for this population.