title: Psychometric validation of the Japanese translation of the Quality of Life in Reflux and Dyspepsia questionnaire in patients with heartburn.
abstract: BACKGROUND
  The purpose of this study was to document the psychometric characteristics of the Japanese translation of the Quality of Life in Reflux and Dyspepsia (QOLRAD-J) questionnaire in patients with heartburn.
  
  
  METHODS
  Patients with heartburn or acid regurgitation and healthy subjects completed the QOLRAD-J and the Japanese version of the Short-Form 36-Item (SF-36) Health Survey.
  
  
  RESULTS
  Overall, 224 patients with heartburn and 24 healthy subjects entered the study; 72% of patients had heartburn 1-3 days per week; 84% reported their symptoms as mild. Psychometric validation of the QOLRAD-J showed that factor loadings were >0.55 for 19 of the 25 items in the five-factor structure. Pearson correlation coefficients for inter-item correlations in the same domain were all >0.30, demonstrating reliability. The internal consistency reliability was good (Cronbach's alpha, 0.83-0.94). Inter-item correlations between domains ranged from 0.70 to 0.80, indicating strong correlations. Each QOLRAD-J domain correlated positively with at least five of the eight SF-36 domains (Pearson r >or= 0.3). Negative correlations between the QOLRAD-J and patient-reported frequency and severity of heartburn symptoms indicated decreasing quality of life with increasing symptoms. All domains of the QOLRAD-J were able to differentiate between groups of patients whose health status differed according to severity and frequency of heartburn, thus confirming the known-groups validity. Patients with heartburn had clinically significant decreases in SF-36 scores compared with the Japanese general population.
  
  
  CONCLUSIONS
  The psychometric characteristics of the QOLRAD-J demonstrated good validity and reliability. The QOLRAD-J can be used to assess quality of life in Japanese patients with heartburn.
authors.affiliation: Department of Comprehensive Medicine, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba, Sendai 980-8574, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Hongo
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kinoshita
authors.forename: Kojiro
authors.initials: K
authors.lastname: Shimozuma
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kumagai
authors.forename: Mitsutaka
authors.initials: M
authors.lastname: Sawada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nii
mesh_terms: D000328:Adult; D000368:Aged; D004415:Dyspepsia / Q000175:diagnosis; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006356:Heartburn / Q000175:diagnosis*; D006801:Humans; D007564:Japan; D007802:Language; D008297:Male; D008875:Middle Aged; D011594:Psychometrics / Q000379:methods*; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires