title: Randomised controlled trials: subgroup analyses.
authors.affiliation: Institute for Medical and Biomedical Education, St George's, University of London, London, UK p.sedgwick@sgul.ac.uk.
authors.forename: Philip
authors.initials: P
authors.lastname: Sedgwick
mesh_terms: D015986:Confounding Factors, Epidemiologic; D006801:Humans; D011482:Protective Devices / Q000706:statistics & numerical data; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D013525:Surgical Instruments / Q000706:statistics & numerical data; D013530:Surgical Wound Infection / Q000517:prevention & control