title: Quality-of-life survey for patients diagnosed with nonmuscle-invasive bladder cancer.
abstract: OBJECTIVE
  To determine the reliability and validity of a quality-of-life survey for patients with nonmuscle-invasive bladder cancer.
  
  
  METHODS
  A total of 180 patients were included in the study. We developed a survey with 21 questions grouped into 5 areas. The patients filled in this survey and the Functional Assessment of Cancer Therapy - Bladder Cancer (FACT-BL) survey. To assess reliability, we calculated Cronbach's alpha coefficient and the kappa index. To determine criterion validity, we studied the association between the scores obtained from our survey and those from the FACT-BL survey using the Pearson correlation coefficient. To determine the construct validity (factorial and discriminatory), we performed a factor analysis, comparing it with Student's t-test for the scores obtained according to the tumour characteristics of reduced quality of life (e.g., malignancies located at the trigone of the bladder).
  
  
  RESULTS
  Cronbach's alpha reliability coefficient was .83, and the kappa index varied between .7 and 1. For the association study between the new survey and the FACT-BL survey, we measured an r=.82 for the overall score and between r=.68 (disease) and r=.97 (sex life) in the various measures. In the factor analysis, we measured a Kaiser-Meyer-Olkin index of .77 and performed the Barlett test (P<.001). The comparison between the scores, in the presence or absence of certain tumour characteristics, has shown a reduced quality of life when those characteristics are present, which was statistically significant (P<.05) in the majority of cases.
  
  
  CONCLUSIONS
  Our survey to measure the quality of life of patients with nonmuscle-invasive bladder cancer is reliable and valid.
authors.affiliation: Servicio de Urología, Hospital General Universitario de Alicante, Alicante, España. Electronic address: iramedi@hotmail.com.
authors.forename: I
authors.initials: I
authors.lastname: Abáigar-Pedraza
authors.affiliation: Servicio de Urología, Hospital General Universitario de Alicante, Alicante, España.
authors.forename: J
authors.initials: J
authors.lastname: Megías-Garrigós
authors.affiliation: Unidad de Epidemiología, Servicio de Medicina Preventiva, Hospital General Universitario de Alicante, Alicante, España.
authors.forename: J
authors.initials: J
authors.lastname: Sánchez-Payá
mesh_terms: D006801:Humans; D009361:Neoplasm Invasiveness; D011788:Quality of Life; D015203:Reproducibility of Results; D057566:Self Report; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis
keywords: Calidad de vida; Cáncer de vejiga superficial; Fiabilidad; Quality of life; Reliability; Superficial bladder cancer; Validez; Validity