title: Development and validation of the Japanese version of the Decisional Conflict Scale to investigate the value of pharmacists' information: a before and after study.
abstract: BACKGROUND
  The information provided in patient-centered care and shared decision-making influences patients' concerns and adherence to treatment. In the decision-making process, patients experience decisional conflict. The Decisional Conflict Scale (DCS) is a 16-item, self-administered questionnaire consisting of 5 subscales developed to assess patients' decisional conflict. This study aimed to develop the Japanese version of the DCS and to clarify the influence of the information provided by pharmacists' on decisional conflict among patients with cancer.
  
  
  METHODS
  We developed the Japanese version of the DCS by using the forward-backward translation method. One hundred patients who were recommended a new chemotherapy regimen were recruited. The psychometric properties of the Japanese DCS, including internal consistency, convergent validity, discriminant validity, and construct validity, were examined. We assessed the decisional conflict of patients before and after the pharmacists' provision of information.
  
  
  RESULTS
  Ninety-four patients, predominately female, with an average age of 58.1 years were sampled. The scores on the 5 subscales of the DCS showed high internal consistency (Cronbach's alpha = 0.84-0.96). Multi-trait scaling analysis and cluster analysis showed strong validity. The mean total DCS score decreased significantly from 40.2 to 31.7 after patients received information from the pharmacists (p < 0.001, paired t-test). Scores on all 5 subscales, namely, uncertainty, informed, values clarity, support, and effective decision, also significantly improved (p < 0.001 for all categories, paired t-test).
  
  
  CONCLUSIONS
  The psychometric properties of the Japanese version of the DCS are considered appropriate for it to be administered to patients with cancer. Pharmacists' provision of information was able to decrease decisional conflict among patients with cancer who were recommended a new chemotherapy regimen.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Kanako
authors.initials: K
authors.lastname: Azuma
authors.forename: Takuhiro
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Soeda
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sekine
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Koinuma
authors.forename: Hironori
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Takao
authors.initials: T
authors.lastname: Akashi
authors.forename: Sakae
authors.initials: S
authors.lastname: Unezaki
mesh_terms: D000328:Adult; D000368:Aged; D003220:Conflict, Psychological; D003657:Decision Making; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000523:psychology / Q000628:therapy; D010342:Patient Acceptance of Health Care / Q000523:psychology*; D010595:Pharmacists / Q000592:standards; D011594:Psychometrics / Q000295:instrumentation*; D011795:Surveys and Questionnaires / Q000592:standards*