title: Cross-cultural validation of the Japanese version of the lung cancer subscale on the functional assessment of cancer therapy-lung.
abstract: BACKGROUND
  The Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire, which consists of a core questionnaire (the General Measure of FACT [FACT-G]) and a 9-item Additional Concerns comprised of a 7-item Lung Cancer Subscale (LCS), was developed in an English-speaking culture. The validation of the Japanese FACT-G was reported previously, and this report describes the cross-cultural validation of the LCS.
  
  
  METHODS
  The Japanese version of the LCS was developed through an iterative forward-backward translation sequence used throughout the FACT Multilingual Translation Project. In evaluating psychometric performance, its construct validity was investigated with Cronbach's alpha coefficient and factor analysis. Clinical validities of a known-groups comparison and longitudinal validity were also investigated.
  
  
  RESULTS
  The FACT-L was administered twice to 180 patients with lung cancer within 2 weeks. The Japanese LCS had borderline values for Cronbachs alpha coefficients (0.62-0.67). Factor analysis indicated that the LCS had the three dimensions of respiratory symptoms, appetite plus body weight, and clear thinking. For clinical validity, a known-groups comparison showed that the LCS could differentiate patients according to truth disclosure, as Japanese doctors sometimes do not fully inform terminally ill patients. However, responsiveness was not proved when performance status was used as an anchor, probably owing to the short interval between the administration of the two measures.
  
  
  CONCLUSIONS
  The Japanese version of the LCS asked questions about multiple symptoms of patients with lung cancer, as did the original English LCS. The longitudinal clinical validity of the Japanese version should be investigated in future clinical trials.
authors: Department of Respiratory Medicine, Saitama Medical University,Saitama, Japan.
authors: Erika
authors: E
authors: Saitoh
authors: Yuki
authors: Y
authors: Yokomizo
authors: Chih-Hung
authors: CH
authors: Chang
authors: Sonya
authors: S
authors: Eremenco
authors: Hiyori
authors: H
authors: Kaneko
authors: Kunihiko
authors: K
authors: Kobayashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003431:Cross-Cultural Comparison; D005260:Female; D006801:Humans; D007564:Japan; D008175:Lung Neoplasms / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D011795:Surveys and Questionnaires; D014175:Translating