title: Reproducibility and Reliability of the Quality of Life Questionnaire in Patients With Atrial Fibrillation.
abstract: BACKGROUND
  Studies have shown the impact of atrial fibrillation (AF) on the patients' quality of life. Specific questionnaires enable the evaluation of relevant events. We previously developed a questionnaire to assess the quality of life of patients with AF (AFQLQ version 1), which was reviewed in this study, and new domains were added.
  
  
  OBJECTIVE
  To demonstrate the reproducibility of the AFQLQ version 2 (AFQLQ v.2), which included the domains of fatigue, illness perception and well-being.
  
  
  METHODS
  We applied 160 questionnaires (AFQLQ v.2 and SF-36) to 40 patients, at baseline and 15 days after, to measure inter- and intraobserver reproducibility. The analysis of quality of life stability was determined by test-retest, applying the Bartko intraclass correlation coefficient (ICC). Internal consistency was assessed by Cronbach's alpha test.
  
  
  RESULTS
  The total score of the test-retest (n = 40) had an ICC of 0.98 in the AFQLQ v.2, and of 0.94 in the SF36. In assessing the intra- and interobserver reproducibility of the AFQLQ v.2, the ICC reliability was 0.98 and 0.97, respectively. The internal consistency had a Cronbach's alpha coefficient of 0.82, compatible with good agreement of the AFQLQ v.2.
  
  
  CONCLUSIONS
  The AFQLQ v.2 performed better than its previous version. Similarly, the domains added contributed to make it more comprehensive and robust to assess the quality of life of patients with AF.
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Rita Simone Lopes
authors.initials: RS
authors.lastname: Moreira
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Bassolli
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Enia
authors.initials: E
authors.lastname: Coutinho
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Paloma
authors.initials: P
authors.lastname: Ferrer
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Érika Olivier
authors.initials: ÉO
authors.lastname: Bragança
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Antonio Carlos Camargo
authors.initials: AC
authors.lastname: Carvalho
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Angelo Amato
authors.initials: AA
authors.lastname: de Paola
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Bráulio
authors.initials: B
authors.lastname: Luna Filho
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000523:psychology*; D005221:Fatigue / Q000523:psychology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010465:Perception; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*