Cross-cultural application of the Korean version of the EORTC QLQ-ELD14 questionnaire for elderly patients with cancer

Objectives The European Organization for Research and Treatment of Cancer (EORTC) QLQ-ELD14 is a validated tool that measures Health-related Quality-of-life (HRQOL) for elderly patients with cancer. This study was conducted to evaluate the psychometric properties of the Korean version of the EORTC QLQ-ELD14 to determine if this tool can be used to evaluate HRQOL for older Korean patients with cancer. Materials and Methods We recruited 439 elderly patients with cancer aged ≥ 60 years from 11 cancer centers and completed the EORTC QLQ-ELD14 questionnaires. The reliability and validity of the EORTC QLQ-ELD14 questionnaire were assessed via Cronbach alpha, multitrait scaling analyses, correlation analyses with the EORTC QLQ-C30, and known-group comparisons. Known-group comparisons were conducted by dividing the patients into groups based on the cancer stage, depression level, and loss of mobility. Results The scale structure of the Korean version of the EORTC QLQ-ELD14 was consistent with the originally hypothesized scale structure. Cronbach alpha coefficients ranged 0.65–0.88. Multitrait scaling analysis showed good item convergent and discriminant validity. Low scaling errors (3.1%) were observed. Divergent validity was demonstrated by no strong correlation with the EORTC QLQ C30. The clinical validity of the Korean version of the EORTC QLQ-ELD14 was demonstrated by its ability to discriminate among patient subgroups categorized by AJCC stage, depression level, and loss of mobility. Conclusion Our findings indicate that the Korean version of the EORTC QLQ-ELD14 questionnaire is reliable and valid for measuring QOL of older Korean patients with cancer.