Brazilian Portuguese validation of the breast cancer-related modules of the BREAST-Q

Background: The rising incidence of breast cancer and the growing number of survivors underscore the need for further research into quality of life. The BREAST-Q is one of the most comprehensive tools for assessing quality of life (QL) in patients undergoing breast surgery. Although translated into multiple languages, it has only been fully validated in English. Material and methods: . Test-retest reproducibility was analyzed using the intraclass correlation coefficient (ICC). Construct validity was evaluated using Spearman's correlation coefficient. Responsiveness to change was assessed using the Wilcoxon test. Comparisons among independent groups, performed using the Kruskal-Wallis test. Convergent and discriminant validity analysis was achieved by comparing the results with those of the BCTOS and EORTC QLQ questionnaires. Results: ≤ -0.4 (negative correlations). Responsiveness showed that the mastectomy without reconstruction group had worse quality of life. Comparisons among independent groups demonstrated, in the postoperative phase, highest QL in the BCT with radiotherapy group. Conclusion: The findings indicate that all breast cancer-related modules of the BREAST-Q effectively measured QL in Brazilian patients.