title: The eortc quality of life questionnaire QLQ-C30 (version 3.0). Validation study for Spanish prostate cancer patients.
abstract: OBJECTIVE
  The EORTC Quality of Life Group has developed a questionnaire for evaluating Quality of Life in international clinical trials: EORTC QLQ-C30, which is widely used in many countries. The purpose of this study was to assess the psychometric properties of the third version of this questionnaire, EORTC QLQ-C30 (version 3.0), when applied to Spanish prostate cancer patients.
  
  
  METHODS
  A sample of 137 prostate cancer patients prospectively filled in the questionnaire three times: on the first and last day of the treatment, and in the followup period. Psychometric evaluation of the structure, reliability and validity was made.
  
  
  RESULTS
  Multitrait scaling analysis showed that most item-scale correlation coefficients met the standards of convergent and discriminant validity. Few exceptions appeared mainly in CF Most scales had low to moderate inter-correlations. Cronbach's coefficients of the scales were above 0.7, except for the CF and NV values. Group comparison analyses showed better QL in patients with higher Performance Status. Changes in functioning and symptom areas appeared throughout the different measurements, which were in line with the treatment process.
  
  
  CONCLUSIONS
  The EORTC QLQC30 (version 3.0) appeared as a reliable and valid instrument when applied to a sample of Spanish prostrate cancer patients. The results are in line with previous studies.
authors.affiliation: Radiotherapeutic Oncology Department, Hospital of Navarre, Irunlarrea, Pamplona, Spain. jiarraras@correo.cop.es
authors.forename: Juan Ignacio
authors.initials: JI
authors.lastname: Arraras Urdaniz
authors.forename: Elena
authors.initials: E
authors.lastname: Villafranca Iturre
authors.forename: Fernando
authors.initials: F
authors.lastname: Arias de la Vega
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Domínguez Domínguez
authors.forename: Nuria
authors.initials: N
authors.lastname: Lainez Milagro
authors.forename: Ana
authors.initials: A
authors.lastname: Manterola Burgaleta
authors.forename: Enrique
authors.initials: E
authors.lastname: Martínez Lopez
authors.forename: Pilar
authors.initials: P
authors.lastname: Romero Rojano
authors.forename: Maite
authors.initials: M
authors.lastname: Martínez Aguillo
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000175:diagnosis; D011788:Quality of Life; D013030:Spain; D011795:Surveys and Questionnaires