Schmidt, Stefanie, 1979-Riel, RicardFrances, AlbertLorente Garin, José AntonioBonfill, XavierMartínez Zapata, María JoséMorales Suárez-Varela, MaríaCruz, Javier de laEmparanza, José IgnacioSánchez, María JoséZamora, JavierGoñi, Juan Manuel RamosAlonso Caballero, JordiFerrer Forés, Maria MontserratEMPARO-CU Study Group2015-06-092015-06-092014Schmidt S, Riel R, Frances A, Lorente Garin JA, Bonfill X, Martínez-Zapata et al. Bladder cancer index: cross-cultural adaptation into Spanish and psychometric evaluation. Health and quality of life outcomes. 2014;12:20. DOI: 10.1186/1477-7525-12-201477-7525http://hdl.handle.net/10230/23775Background: The Bladder Cancer Index (BCI) is so far the only instrument applicable across all bladder cancer patients, independent of tumor infiltration or treatment applied. We developed a Spanish version of the BCI, and assessed its acceptability and metric properties. Methods: For the adaptation into Spanish we used the forward and back-translation method, expert panels, and cognitive debriefing patient interviews. For the assessment of metric properties we used data from 197 bladder cancer patients from a multi-center prospective study. The Spanish BCI and the SF-36 Health Survey were self-administered before and 12 months after treatment. Reliability was estimated by Cronbach’s alpha. Construct validity was assessed through the multi-trait multi-method matrix. The magnitude of change was quantified by effect sizes to assess responsiveness./nResults: Reliability coefficients ranged 0.75-0.97. The validity analysis confirmed moderate associations between the BCI function and bother subscales for urinary (r = 0.61) and bowel (r = 0.53) domains; conceptual independence among all BCI domains (r ≤ 0.3); and low correlation coefficients with the SF-36 scores, ranging 0.14-0.48. Among patients reporting global improvement at follow-up, pre-post treatment changes were statistically significant for the urinary domain and urinary bother subscale, with effect sizes of 0.38 and 0.53. Conclusions: The Spanish BCI is well accepted, reliable, valid, responsive, and similar in performance compared to the original instrument. These findings support its use, both in Spanish and international studies, as a valuable and comprehensive tool for assessing quality of life across a wide range of bladder cancer patients.application/pdfeng© 2014 Schmidt et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Bufeta -- Càncerinfo:eu-repo/semantics/articlehttp://dx.doi.org/10.1186/1477-7525-12-20Urinary bladder neoplasmsQuality of lifePatient outcomesValidation studiesPsychometricsinfo:eu-repo/semantics/openAccess