Abstract PO3-11-09: Cross-cultural adaptation and psychometric validation of lymphedema patient-reported outcome measurements in Chinese breast cancer patients
Authors: Zhou Yue , Xiu Bingqiu , Zhang Qi , Wu Jiong 
Published: May 2024

Abstract
Background: Lymphedema is one of the most common complains reported by breast cancer survivors, which negatively affects the quality of life (QoL). Various internationally recognized patient-reported outcome measurements (PROMs), such as the Upper Limb Lymphedema 27 (ULL-27), Lymphoedema Functioning, Disability and Health questionnaire (Lymph-ICF), Lymphedema Quality of Life Questionnaire for upper limbs (LYMQOL-ARM), and Lymphedema Life Impact Scale Version 2 (LLIS), have been translated into different languages and widely used to assess QoL in patients with breast cancer-related lymphedema (BCRL). However, limited evidence has proved the efficiency of these tools in Chinese patients. In this study, we performed cross-cultural adaptation and psychometric validation of these four PROMs within the Chinese context. Additionally, we also compared the accuracy in detecting BCRL for early diagnosis. Methods: A process of forward–backward translation and cultural adaptation was conducted based on international standards. Content validity was assessed through patient interviews. Internal consistency was evaluated by Cronbach’s alpha coefficient. The correlation analysis of the MOS item short from health survey (SF-36) and each BCRL QoL questionnaires was utilized to indicate the convergent and divergent validity. Clinical validity was assessed by comparing scores among patients with different BCRL stages. Furthermore, questionnaires scores and the known group of lymphedema or not were compared to generate receiver operator characteristic (ROC) curves of these instruments. Results: A total of 204 female breast cancer patients were recruited in this study. Among them, 104 patients (61 with lymphedema and 43 without lymphedema) finished LYMQOL-ARM and ULL-27 questionnaire, while 100 patients (59 with lymphedema and 41 without lymphedema) were assessed by Lymph-ICF and LLIS. The internal consistency was high, with Cronbach's alpha coefficients above 0.9 for all subscales and global scales. The content validity was generally good, except for a few issues reported by the patients. Convergent and divergent validity confirmed the hypotheses of correlation between the tested questionnaire and SF-36 to varying degrees: 100% for ULL-27, 80% for Lymph-ICF, nearly 70% for LLIS, and only 50% for LYMQOL-ARM. LLIS and Lymph-ICF demonstrated strong clinical validity, with significant differences found in total and subscale scores among participants in different BCRL stages (P&lt; 0.05). There were no significant differences between stages for the mood dimension (P=0.132) of LYMQOL-ARM, psychological dimension (P=0.506), social dimension (P=0.083), and total score (P=0.057) of ULL-27. Only the physical concerns and global scale of LLIS and the symptom subscale of Lymph-ICF exhibited acceptable AUC values near 0.7 (AUC 0.725, 95% CI 0.625-0.825, p&lt; 0.029; AUC 0.680, 95% CI 0.573-0.787, p&lt; 0.002; AUC 0.734, 95% CI 0.633-0.834, p&lt; 0.001, respectively). In contrast, other subscales and questionnaires displayed lower AUC values. Conclusion: Lymphedema is a chronic disease that has a relatively low mortality risk but significantly affects the quality of life. Therefore, it is crucial to prioritize patient-reported outcomes in the assessment of lymphedema. Among the four PROMs, LLIS not only showed high internal consistency and content validity more suitable for Chinese patients, but also exhibited better performance in reflecting the presence and severity of lymphedema patients. Consequently, the validated and reliable Chinese version of LLIS is recommended for clinical and scientific practices in the assessment of BCRL, which will help to provide better interventions with a patient-centered focus.
Citation Format: Yue Zhou, Bingqiu Xiu, Qi Zhang, Jiong Wu. Cross-cultural adaptation and psychometric validation of lymphedema patient-reported outcome measurements in Chinese breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-11-09.