title: Verification of the psychometric properties of the Japanese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 15 palliative (EORTCQLQ-C15-PAL).
abstract: OBJECTIVE
  We compared Japanese versions of the EORTC QLQ-C15-PAL and QLQ-C30 to assess the utility of the former survey for terminal-phase cancer patients.
  
  
  METHODS
  We used QLQ-C30 scores from the survey prior to each patient's death and extracted QLQ-C15-PAL data. We determined intraclass correlation coefficients (ICCs) of the five QLQ-C15-PAL subscales: physical functioning, emotional functioning, fatigue, nausea and vomiting, and global health status/quality of life (QOL) and assessed equivalent-form reliability. Regression analysis was used to determine the extent to which QLQ-C15-PAL items explained the QLQ-C30 score.
  
  
  RESULTS
  Our study included 32 of 91 cancer patients receiving palliative care who could self-administer the questionnaire. The ICC between the QLQ-C15-PAL and QLQ-C30 scores was 0.93 or higher. The proportion of variance (R-squared) for each subscale was 0.87 or higher.
  
  
  CONCLUSIONS
  We examined the validity and reliability of the Japanese version of the QLQ-C15-PAL. We found an 87% or higher chance that the QLQ-C15-PAL could explain the original QLQ-C30 score. Therefore, QLQ-C15-PAL appears to be useful for assessing the QOL of terminal-phase cancer patients.
authors.affiliation: Department of Health Informatics, School of Public Health, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan. miy@plum.ocn.ne.jp
authors.forename: Kikuko
authors.initials: K
authors.lastname: Miyazaki
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Suzukamo
authors.forename: Kojiro
authors.initials: K
authors.lastname: Shimozuma
authors.forename: Takeo
authors.initials: T
authors.lastname: Nakayama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006304:Health Status; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000523:psychology* / Q000628:therapy; D010166:Palliative Care / Q000523:psychology*; D011594:Psychometrics / Q000379:methods*; D011788:Quality of Life; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D055815:Young Adult