title: Translation and psychometric evaluation of the simplified Chinese-version Endometriosis Health Profile-30.
abstract: OBJECTIVE
  What are the psychometric properties in mainland China of the 30-item Endometriosis Health Profile (EHP-30) translated into simplified Chinese?
  
  
  CONCLUSIONS
  The simplified Chinese version of the EHP-30 is a valid, reliable and acceptable tool for the measurement of the health-related quality of life (HRQoL) of women with endometriosis in the context of mainland China.
  
  
  BACKGROUND
  Endometriosis can critically affect women's HRQoL. The EHP-30 is currently the most reliable instrument to measure the HRQoL in women with endometriosis.
  
  
  METHODS
  This cross-sectional study was conducted in a tertiary referral university hospital from February 2012 to August 2012 in Beijing, P. R. China.
  
  
  METHODS
  The translation and cultural adaptation of the EHP-30 was performed according to accepted guidelines. The study included 336 women with endometriosis. Psychometric evaluation included factor analysis, convergent validity, measurement of internal consistency, item-total correlations and data completeness, descriptive statistics, and the determination of floor and ceiling effects.
  
  
  RESULTS
  Factor analysis confirmed the validity of the five-factor structure of the EHP-30 core questionnaire, which explained 79.51% of the total variance. The correlations of related subscale scores between EHP-30 and Short Form-36 were all significant. Cronbach's α for internal consistency across each scale ranged 0.89-0.97 for the core questionnaire and 0.80-0.96 for the modular questionnaire. No <97.67% of data completeness was achieved. Floor effects were observed in three scales: self-image (19.64%), children (26.67%) and medical profession (15.19%). No ceiling effects were found. The control and powerlessness scale had the highest median score (54.17) in the core questionnaire, whereas the infertility module (median = 56.25) had the highest score in the modular section.
  
  
  CONCLUSIONS
  The study was conducted in a referral centre for the treatment of endometriosis, thereby leading to overrepresentation of severe symptoms of endometriosis. Furthermore, the test-retest reliability and responsiveness of the questionnaire were not evaluated in this study.
  
  
  CONCLUSIONS
  Our study addresses the urgent need for a valid and reliable instrument to measure the HRQoL of female patients with endometriosis in mainland China.
  
  
  BACKGROUND
  This work was supported by grants to J. Leng from the Key Project for Clinical Faculty Foundation, Ministry of Health, China (2010). None of the authors has any conflict of interest to declare.
authors.affiliation: Department of Obstetrics and Gynecology,  Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing,  P. R. China.
authors.forename: Shuang-Zheng
authors.initials: SZ
authors.lastname: Jia
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Leng
authors.forename: Peng-Ran
authors.initials: PR
authors.lastname: Sun
authors.forename: Jing-He
authors.initials: JH
authors.lastname: Lang
mesh_terms: D000328:Adult; D002681:China; D003430:Cross-Sectional Studies; D004715:Endometriosis / Q000208:ethnology / Q000503:physiopathology* / Q000523:psychology*; D005163:Factor Analysis, Statistical; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007247:Infertility, Female / Q000209:etiology; D007802:Language; D008875:Middle Aged; D010865:Pilot Projects; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000379:methods; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D055815:Young Adult