title: HIV and male circumcision--a systematic review with assessment of the quality of studies.
abstract: This Cochrane systematic review assesses the evidence for an interventional effect of male circumcision in preventing acquisition of HIV-1 and HIV-2 by men through heterosexual intercourse. The review includes a comprehensive assessment of the quality of all 37 included observational studies. Studies in high-risk populations consisted of four cohort studies, 12 cross-sectional studies, and three case-control studies; general population studies consisted of one cohort study, 16 cross-sectional studies, and one case-control study. There is evidence of methodological heterogeneity between studies, and statistical heterogeneity was highly significant for both general population cross-sectional studies (chi(2)=132.34; degrees of freedom [df]=15; p<0.00001) and high-risk cross-sectional studies (chi(2)=29.70; df=10; p=0.001). Study quality was very variable and no studies measured the same set of potential confounding variables. Therefore, conducting a meta-analysis was inappropriate. Detailed quality assessment of observational studies can provide a useful visual aid to interpreting findings. Although most studies show an association between male circumcision and prevention of HIV, these results may be limited by confounding, which is unlikely to be adjusted for.
authors.affiliation: South African Cochrane Centre, Medical Research Council, South Africa. nsiegfried@cochrane.co.uk
authors.forename: N
authors.initials: N
authors.lastname: Siegfried
authors.forename: M
authors.initials: M
authors.lastname: Muller
authors.forename: J
authors.initials: J
authors.lastname: Deeks
authors.forename: J
authors.initials: J
authors.lastname: Volmink
authors.forename: M
authors.initials: M
authors.lastname: Egger
authors.forename: N
authors.initials: N
authors.lastname: Low
authors.forename: S
authors.initials: S
authors.lastname: Walker
authors.forename: P
authors.initials: P
authors.lastname: Williamson
mesh_terms: D017954:Africa South of the Sahara / Q000453:epidemiology; D002944:Circumcision, Male; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D015497:HIV-1; D015498:HIV-2; D006801:Humans; D008297:Male; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D012725:Sexual Behavior