title: Health-related quality of life in patients with lung cancer: validation of the Mexican-Spanish version and association with prognosis of the EORTC QLQ-LC13 questionnaire.
abstract: BACKGROUND
  Lung cancer (LC) is the first cause of cancer-related mortality worldwide and health-related quality of life (HRQL) is a fundamental outcome for evaluating treatment results. Our objective was to validate the Mexican-Spanish versions of the European Organisation for Research and Treatment of Cancer (EORTC) Quality-of-Life QLQ-LC13 disease-specific questionnaire module in Mexican patients with LC; and to explore the possible prognostic role of HRQL data.
  
  
  METHODS
  Translation procedures followed EORTC guidelines. Both instruments were completed by patients with LC. Tests for reliability and validity were performed. A subset of patients was administered HRQL evaluations before and after chemotherapy. HRQL was associated with prognosis in chemotherapy-naïve patients. The protocol was approved by the Institute's Ethics Committee.
  
  
  RESULTS
  One hundred fifty three patients (mean age, 60.3 years; 84 females and 69 males) completed both questionnaires. Compliance rates were high, and the questionnaires were well accepted. Nine of 10 multi-item scales of both questionnaires presented Cronbach's alpha coefficients > 0.7. Multi-trait scaling analysis demonstrated good convergent and discriminant validity. Patients with better Karnofsky or Eastern Cooperative Oncology Group (ECOG) performance status reported better functional HRQL scores. Different scales in the EORTC QLQ-C30 and EORTC QLQ-LC13 questionnaires were accurately related with clinical characteristics. Functional as well as disease-symptom scales improved after chemotherapy, but treatment side-effects scales worsened in test-retest analysis. Better role functioning and absence of thoracic pain scales were associated with longer overall survival (OS) (p = 0.009 and p = 0.035, respectively).
  
  
  CONCLUSIONS
  The Mexican-Spanish versions of the EORTC QLQ-C30 and EORTC QLQ-LC13 questionnaires are reliable and valid for HRQL measurement in Mexican patients with LC and can be used in clinical trials.
authors.affiliation: Clínica de Cáncer de Pulmón, Instituto Nacional de Cancerología, Mexico City, Mexico.
authors.forename: Óscar
authors.initials: Ó
authors.lastname: Arrieta
authors.forename: Carolina
authors.initials: C
authors.lastname: Núñez-Valencia
authors.forename: Leonardo
authors.initials: L
authors.lastname: Reynoso-Erazo
authors.forename: Salvador
authors.initials: S
authors.lastname: Alvarado
authors.forename: Diana
authors.initials: D
authors.lastname: Flores-Estrada
authors.forename: Laura Patricia
authors.initials: LP
authors.lastname: Angulo
authors.forename: Luis F
authors.initials: LF
authors.lastname: Oñate-Ocaña
mesh_terms: D000368:Aged; D002283:Carcinoma, Bronchogenic / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D017567:Karnofsky Performance Status; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D018655:Lymphocyte Count; D008297:Male; D008654:Mesothelioma / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D008800:Mexico; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D011788:Quality of Life; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires; D016896:Treatment Outcome