Psychometric Properties of the Turkish Version of the LYMPH-Q Upper Extremity Module with Breast Cancer-Related Lymphedema Patients: Validity, Reliability, and Responsiveness

Background: Although several patient-reported outcome measures (PROMs) exist to assess health-related quality of life (HRQoL) in patients with breast cancer-related lymphedema (BCRL), most lack sufficient patient input. The LYMPH-Q Upper Extremity (UE) module was developed to address this gap, providing a comprehensive assessment of BCRL from the patient’s perspective. The aim of this study was to adapt LYMPH-Q Upper UE module into Turkish and to evaluate its psychometric properties in patients with BCRL. Methods and Results: A total of 91 women with unilateral BCRL were included in the present study. Reliability analyses using Cronbach’s alpha and intraclass correlation coefficients (ICC). Convergent validity was assessed using upper Limb Lymphedema Quality of Life Questionnaire (ULL-27), Lymphedema Quality of Life Questionnaire-Arm (LYMQOL-Arm) and Short Form 36-item Health Survey Instrument (SF-36). Responsiveness was assessed by changes in LYMPH-Q UE module domains to complex decongestive therapy (CDT). The LYMPH-Q UE module showed strong internal consistency with Cronbach’s alpha values ranging from 0.850 to 0.956 and ICC values between 0.80 and 0.94, indicating good to excellent reproducibility. Convergent validity was confirmed with poor to strong correlations (r = −0.308 to −0.871) between the LYMPH-Q UE module and ULL-27 and LYMQOL-Arm. The responsiveness of the LYMPH-Q UE module to CDT showed significant improvements in symptoms ( p < 0.001, d = 1.90), function ( p < 0.001, d = 1.27), appearance ( p = 0.001, d = 1.10), psychological ( p < 0.001, d = 0.68), and knowledge ( p < 0.001, d = 2.80), except for the arm sleeve domain ( p = 0.792, d = 0.10). Conclusion: The Turkish LYMPH-Q UE module has adequate psychometric properties to assess HRQoL in BCRL patients.