title: Validity of the CAGE questionnaire for men who have sex with men (MSM) in China.
abstract: BACKGROUND
  Detection of heavy drinking among men who have sex with men (MSM) is crucial for both intervention and treatment. The CAGE questionnaire is a popular screening instrument for alcohol use problems. However, the validity of CAGE for Chinese MSM is unknown.
  
  
  METHODS
  Data were from three waves of cross-sectional assessments among general MSM (n=523) and men who sell sex to other men ("money boys" or MBs, n=486) in Shanghai, China. Specifically, participants were recruited using respondent-driven, community popular opinion leader, and venue-based sampling methods. The validity of the CAGE was examined for different cutoff scores and individual CAGE items using self-reported heavy drinking (≥14 drinks in the past week) as a criterion.
  
  
  RESULTS
  In the full sample, 75 (7.4%) of participants were classified as heavy drinkers. 32 (6.1%) of general MSM and 43 (8.9%) of MBs were heavy drinkers. The area under curve statistics for overall sample was 0.7 (95% CI: 0.36-0.77). Overall, the sensitivities (ranging from 18.7 to 66.7%), specificities (ranging from 67.5 to 95.8%), and positive predictive values (ranging from 14.1 to 26.4%) for different cutoff scores were inadequate using past week heavy drinking as the criterion. The ability of CAGE to discriminate heavy drinkers from non-heavy drinkers was limited.
  
  
  CONCLUSIONS
  Our findings showed the inadequate validity of CAGE as a screening instrument for current heavy drinking in Chinese MSM. Further research using a combination of validity criteria is needed to determine the applicability of CAGE for this population.
authors: Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, United States.
authors: Yen-Tyng
authors: YT
authors: Chen
authors: Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, United States.
authors: Umedjon
authors: U
authors: Ibragimov
authors: Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, United States. Electronic address: enehl@emory.edu.
authors: Eric J
authors: EJ
authors: Nehl
authors: Shanghai Piaoxue, Shanghai, China.
authors: Tony
authors: T
authors: Zheng
authors: Department of Epidemiology, Fudan University School of Public Health, Shanghai, China.
authors: Na
authors: N
authors: He
authors: Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, United States.
authors: Frank Y
authors: FY
authors: Wong
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000175:diagnosis* / Q000523:psychology; D002681:China; D003430:Cross-Sectional Studies; D018451:Homosexuality, Male / Q000523:psychology / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires / Q000592:standards*
keywords: CAGE; China; MSM; Validity