title: Limitations of analyses of effectiveness using observational data.
authors.forename: Barnaby C
authors.initials: BC
authors.lastname: Reeves
mesh_terms: D000368:Aged; D003627:Data Interpretation, Statistical; D006304:Health Status; D006801:Humans; D009204:Myocardial Revascularization / Q000706:statistics & numerical data*; D011788:Quality of Life; D015983:Selection Bias; D016896:Treatment Outcome