Psychometric Properties of the EORTC QLQ-LC29 Module for Assessing Quality of Life in Patients with Lung Cancer: An Observational Study in Antioquia, Colombia.

PURPOSE: The purpose of this study is to evaluate the psychometric properties of the Spain Spanish version of the European Organisation for Research and Treatment of Cancer - Quality of Life Questionnaire - Lung Cancer Module-29 (EORTC QLQ-LC29) in Colombia. METHODS: Content validity was assessed with confirmatory factor analysis, concurrent criterion validity by comparing scores of the QLQ-LC29 and Functional Assessment of Cancer Therapy - Lung (FACT-L) scales, internal consistency by Cronbach's alpha, test-retest reliability with Lin's concordance coefficient, and sensitivity to change after therapeutic intervention by comparing averages in repeated measurements. RESULTS: The EORTC QLQ-LC29 was administered to 292 patients aged 19 to 92 years with a diagnosis of lung cancer. Factor analysis showed acceptable model fit. In the concurrent validity assessment, a significant moderate negative correlation was found between the QLQ-LC29 domains of cough symptoms (-0.499), dyspnea (-0.468), and well-being in the FACT-L module. A moderate negative correlation was also found between fear of disease progression (-0.554) and emotional well-being on the FACT-L scale; Cronbach's alpha of the overall scale was 0.81; Lin's coefficient was between 0.54 and 0.98; differences between scores before and after a therapeutic intervention were significant only for the domain "Side effects of treatment". CONCLUSION: Cultural adaptation of the Spain version of the EORTC QLQ-LC29 was necessary to ensure its internal consistency, stability, feasibility, content validity, criterion validity, and construct validity for measuring quality of life in Colombian lung cancer patients.