The Impact of Time and Place on BREAST‐Q REACT: A Multi‐Institutional Examination

BACKGROUND: Reference values provide clinically meaningful context for interpreting patient-reported outcome measures. However, these values may evolve over time with changes in reconstructive practice and may differ across cultural settings. This study compares BREAST-Q scores across time periods and countries. METHOD: Patients who underwent postmastectomy breast reconstruction and completed the BREAST-Q at Memorial Sloan Kettering Cancer Center (MSKCC) and Maastricht University Medical Center (MUMC +) between 2007 and 2022 were included. BREAST-Q scores from an original MSKCC cohort (2007-2017) were compared with a recent MSKCC cohort (2018-2022) to evaluate temporal differences, and with a Dutch cohort (2013-2022) to assess geographic variation. RESULTS: A total of 7,199 MSKCC patients (3,243 original; 3,956 recent), and 444 MUMC+ patients were included. Compared with the original MSKCC cohort, the recent cohort demonstrated improved Physical Well-being of the Chest among implant-based reconstruction patients at preoperative (81 [74, 91] vs. 85 [74, 100]) and at 2-years postoperative (76 [66, 85] vs. 80 [64, 92]). Other BREAST-Q domains, on the other hand, declined in both implant-based and autologous reconstruction groups. Compared with MSKCC patients, the Dutch cohort reported lower Physical Well-being of the Chest, but higher Sexual Well-being. For example, at 2-years postoperative, MUMC+ patients scored 10 points higher on Sexual Well-being than MSKCC patients (60 [47, 72] vs. 50 [36, 66], p < 0.001). CONCLUSION: BREAST-Q reference values vary over time and across cultural contexts. Contemporary population-specific reference values may improve interpretation of patient-reported outcomes.