Preliminary evaluation of the Polish version of the EORTC QLQ-MY20 module for assessing quality of life in patients with multiple myeloma

Introduction: Multiple myeloma (MM) is a malignant disease originating from plasma cells, characterized by a heterogeneous course and a significant impact on patients’ quality of life. In order to comprehensively assess this impact, specialized measurement tools such as the EORTC QLQ-MY20 are used. This study focuses on the preliminary evaluation of the psychometric properties of the Polish version of this questionnaire, with particular emphasis on its factor structure, reliability, and validity. Material and methods: The analysis was conducted on a sample of 32 patients aged 44 to 77 years (M = 63.31; SD = 9.29). Study participants completed the EORTC QLQ-MY20 module designed for patients with MM, together with the general questionnaire used to assess quality of life in patients with various types of cancer, the EORTC QLQ-C30. Standardized scales assessing pain intensity, anxiety level, and satisfaction with appearance, as well as a demographic questionnaire, were also included. Results: The obtained values of Cronbach’s alpha coefficient (0.75–0.85) confirm good internal reliability of the EORTC QLQ-MY20 questionnaire. Moreover, the applied methods of assessing the validity of the measurement tool confirmed the existence of satisfactory validity. At the same time, the analysis of the factor structure revealed certain ambiguities, indicating the need for further research to determine the optimal factor structure. Conlusions: The Polish version of the EORTC QLQ-MY20 module appears to be a useful tool that requires further verification for measuring health-related quality of life in patients with MM. It may be effectively used both in clinical research and in clinical practice, supporting the assessment of health status and monitoring of patients’ quality of life in everyday oncological care. Nevertheless, the analysis of the factor structure revealed certain discrepancies, suggesting the need for further verification of the theoretical model of the tool.