title: Development and psychometric validation of the Chinese version of Skindex-29 and Skindex-16.
abstract: BACKGROUND
  Dermatological disease significantly affects patient's health-related quality of life (HrQoL). Skindex is one of the most frequently used dermatology-specific HrQoL measures. Currently no Chinese version of Skindex is available. The aim of this study was to translate and culturally adapt Skindex-29 and Skindex-16 into Chinese, and to evaluate their reliability and validity.
  
  
  METHODS
  Translation and cultural adaption were performed following guidelines for cross-cultural adaption of health-related quality of life measures. Subsequently, a cross-sectional study was conducted in which patients with dermatological disease (n = 225) were enrolled. The Chinese version of Skindex-29 and Skindex-16 and Dermatology Life Quality Index (DLQI) were completed. Reliability was evaluated with internal consistency using Cronbach's alpha. Validity was evaluated using known-groups validity, convergent validity and factor structure validity.
  
  
  RESULTS
  There were both seven items of Skindex-29 and Skindex-16 requiring a second forward- and backward- translation to achieve the final satisfactory Chinese version. The internal consistency reliability was high (range of Cronbach's alpha for the scales of Skindex-29 0.85-0.97, Skindex-16 0.86-0.96). Known-group validity was demonstrated by higher scores from patients with inflammatory dermatosis than from patients with isolated skin lesions (P < 0.05). Evidence of factor structure validity of the Skindex-29 and Skindex-16 was demonstrated by both exploratory factor analysis that accounted for 68.66% and 77.78% of the total variance, respectively, and confirmatory factor analysis with acceptable fitness into the expected three-factor structure.
  
  
  CONCLUSIONS
  This study has developed semantically equivalent translations of Skindex-29 and Skindex-16 into Chinese. The evaluation of the instruments' psychometric properties shows they have substantial evidence of reliability and validity for use as HrQoL instruments in Chinese patients with dermatological disease.
authors.affiliation: Department of Clinical Epidemiology, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China. hezehui106@163.com.
authors.forename: Zehui
authors.initials: Z
authors.lastname: He
authors.affiliation: Department of Dermatology, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, No.111 Da De Road, Guangdong, 510120, China. luchuanjian888@vip.sina.com.
authors.forename: Chuanjian
authors.initials: C
authors.lastname: Lu
authors.affiliation: Department of Dermatology, University of California, San Francisco, USA. ChrenM@derm.ucsf.edu.
authors.forename: Mary-Margaret
authors.initials: MM
authors.lastname: Chren
authors.affiliation: Department of Dermatology, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, No.111 Da De Road, Guangdong, 510120, China. 546230396@qq.com.
authors.forename: Zhongzhao
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Sleep and Mental Disorder, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China. janeliyan2002@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Evidence-based Medicine and Clinical Research of Chinese Medicine, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China. grace1984325@126.com.
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Ni
authors.affiliation: Michigan Association of Acupuncture and Oriental Medicine, The Lotus Center of Ann Arbor, Ann Arbor, USA. henry.buchtel@gmail.com.
authors.forename: Henry A
authors.initials: HA
authors.lastname: Buchtel V
authors.affiliation: Department of Neurology, Lutheran Medical Center, New York, USA. zhongdao@live.com.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Ryan
authors.affiliation: Department of Clinical Epidemiology, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China. gzli@tongji.edu.cn.
authors.forename: Guo-Zheng
authors.initials: GZ
authors.lastname: Li
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005163:Factor Analysis, Statistical; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012871:Skin Diseases / Q000523:psychology*; D011795:Surveys and Questionnaires; D014177:Translations; D055815:Young Adult