乳腺癌是全球最重要的健康问题之一。生活质量（QoL）是评估癌症患者症状的重要指标，包括乳腺癌患者。需要符合文化、可信、可靠和适当的工具来测量乳腺癌患者的QoL，这在印度尼西亚仍然很少。本研究旨在将EORTC QLQ-BR45问卷翻译成印尼语并评价其心理测量特性。在转译医学部门方便地选取的635位患者中进行横断面研究。本研究的第一阶段涉及将现有的EORTC QLQ-BR45翻译成印尼语，第二阶段对其心理测量特性进行了评估。使用验证性因子分析（CFA）评估建构效度。根据疾病阶段和Karnofsky绩效评定表（KPS）之间的关联进行标准效度检查。共有635名（99.00％）成功完成了EORTC QLQ-BR45问卷。该问卷具有良好的可读性和高的内容效度。所有Cronbach的阿尔法系数均令人满意（总体值为0.87）。对于构建有效性，KPS≥80％的患者表现比KPS≤70％的患者更好，功能量表中的两个多项量表（身体形象和乳房满意度）以及症状量表中的五个多项量表（系统性治疗副作用、内分泌治疗、臂、乳房和内分泌性症状）也是如此。晚期患者的身体形象评分显著较高。CFA表明印尼EORTC QLQ-BR45的九因素结构适合数据。印尼EORTC QLQ-BR45问卷可靠、有效，并具有良好的心理测量特性，因此可用于印度尼西亚的乳腺癌患者。版权所有©2023年的Solikhah、Perwitasari和Rejeki。

Breast cancer is one of the most important health problems worldwide. Quality of life (QoL) is an important indicator to evaluate symptoms in cancer patients, including those with breast cancer. Culturally suitable, valid, reliable, and appropriate instruments to measure the QoL of breast cancer patients are needed, which is still rare in Indonesia. This study aimed to translate the EORTC QLQ-BR45 instrument into Indonesian and evaluate its psychometrics.A cross-sectional study was performed on 635 patients conveniently selected from the oncology department in referral hospital. The first phase of this study involved translation of the existing EORTC QLQ-BR45 into Indonesian, and in the second phase, we evaluated its psychometric properties. Construct validity was evaluated using confirmatory factor analysis (CFA). Criterion validity was examined according to the association between disease stage and Karnofsky Performance Scale (KPS).A total of 635 (99.00%) completed the EORTC QLQ-BR45 successfully. The instrument indicated good readability and high content validity. All Cronbach's alpha coefficients were satisfactory (overall value, 0.87). For construct validity, patients with KPS ≥80% did better than those with KPS ≤70% as did two multi-item scales in functional scales (body image and breast satisfaction) and five multi-item scales in symptom scales (systemic therapy side effects, endocrine therapy, and arm, breast, and endocrine sexual symptoms). Body image score of late-stage patients was significantly higher. CFA indicated that the nine-factor structure of the Indonesian EORTC QLQ-BR45 was a good fit for the data.The Indonesian EORTC QLQ-BR45 questionnaire is reliable and valid with good psychometric properties, thus can be used for breast cancer patients in Indonesia.Copyright © 2023 Solikhah, Perwitasari and Rejeki.