title: Validity and reliability of the Japanese version of the Patient Assessment of Constipation Quality of Life questionnaire.
abstract: BACKGROUND
  This study aimed to provide a psychometric evaluation of the Japanese version of the Patient Assessment of Constipation Quality of Life questionnaire (JPAC-QOL).
  
  
  METHODS
  Data for scoring were collected prospectively from patients with constipation who visited our center from 2008 to 2010, and analyzed retrospectively. Reliability of the JPAC-QOL was evaluated using Cronbach's alpha to calculate internal consistency, and a test-retest study was performed to evaluate reproducibility. For concurrent validity assessment, the JPAC-QOL scores were compared with Constipation Scoring System (CSS) scores. In assessing responsiveness, the JPAC-QOL scores before and after treatments were compared in patients whose modified CSS (mCSS) scores decreased by >50 %.
  
  
  RESULTS
  Internal consistency was assessed in 295 patients (165 women; mean age 67.0 years). Cronbach's alpha was >0.7 for the overall score and all four subscales, showing a strong internal consistency. The intraclass correlations for the 145 patients available for the test-retest study were >0.7 for the overall score and for all subscales except satisfaction. The JPAC-QOL scores were significantly associated with the CSS scores in 284 patients, demonstrating concurrent validity in all four subscales and the overall score. The mean JPAC-QOL score improved significantly after treatment in the 72 patients whose mCSS scores decreased by >50 %, indicating good responsiveness in all four subscales and in the overall score.
  
  
  CONCLUSIONS
  Our study data confirmed the validity and reliability of the JPAC-QOL and demonstrated it ready for use in evaluating the symptom-specific QOL in Japanese patients with constipation.
authors: Department of Nursing, Kochi Medical School, Kochi University, Kohasu, Oko-cho, Nankoku, Kochi, 783-8505, Japan.
authors: Haruka
authors: H
authors: Nomura
authors: Takeshi
authors: T
authors: Agatsuma
authors: Toshiki
authors: T
authors: Mimura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003248:Constipation / Q000523:psychology*; D005260:Female; D006801:Humans; D007564:Japan; D007802:Language; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
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