A prospective study to validate the Polish language version of the European Organisation for Research and Treatment of Cancer (EORTC) Colorectal Liver Metastases (QLQ-LMC21) module

Purpose: This validation study was designed to assess the psychometric validity and quality of the Polish translation of the EORTC QLQ-LMC21 questionnaire in Polish colorectal patients suffering with liver metastases. Methods: Patients with either histopathological or imaging confirmation of colorectal cancer with liver metastases, with a minimum of three months survival, were eligible for this study. These patients completed the Polish version of the EORTC core QLQ-C30, the QLQ-LMC21 module, and a demographic data questionnaire. The questionnaires were completed twice, once before undergoing either hepatectomy (n = 63) or palliative treatment (n = 97) and three months after the primary treatment. Standardized analyses of validity and reliability were performed. Results: One hundred and sixty patients were enrolled in this study with the mean age of the hepatectomy group 64.3 14.1 and 66.1 +/- 12.7 for the palliative treatment group. The QLQ-LMC21 exhibited positive internal consistency with Cronbach's alpha coefficients ranging from 0.72 to 0.90. The multi-trait scaling analysis demonstrated adequate convergent and discriminant validity. Test-retest reliability was undertaken with 40 patients (25%) with the ICCs for each item ranging from 0.64 to 0.88. The hepatectomy group had a significantly greater Karnofsky Performance Score than the palliative treatment group (p.<0.001). Overall there were weak correlations between the two questionnaires which confirm that the QLQ-LMC21 addresses health issues not assessed in the QLQ-C30. Conclusion: The Polish version of the QLQ-LMC21 proved to be a valid and reliable questionnaire to use in conjunction with the QLQ-C30 core questionnaire. (C) 2017 Elsevier Ltd. All rights reserved.