The Portuguese version, cross-cultural adaptation and validation of specific quality-of-life questionnaire -AQUAREL - for pacemaker patients

To translate, to make the cultural adaptation and to evaluate reproducibility and validity of the Portuguese version of the AQUAREL (Assessment of QUAlity of life and RELated events) questionnaire, which is a specific tool to assess quality of life in pacemaker patients. We evaluated 202 pacemaker patients: 63 patients during the cross-cultural adaptation stage and 139 during the reproducibility and validity evaluation stages. The questionnaire translation was reviewed repeatedly until > or = 85% of patients correctly understood the questions. Reproducibility of the final version was tested in 69 patients in whom the interview was performed twice by the same researcher. Validity was checked by the correlation between scores obtained in AQUAREL domains and those obtained in SF36 domains, in the functional class and the distance walked in the six-minute test. The internal consistency of AQUAREL was adequate, with Cronbachs alpha coefficient varying between 0.59 and 0.85. Reproducibility was good, with high correlation coefficients (0.68-0.89) and random distribution of data in Bland and Altman plots, without systematic bias. A significant association was observed among AQUAREL domains and those obtained in SF36 domains and the functional class (p