title: Causality inference in observational vs. experimental studies. An empirical comparison.
authors.affiliation: Department of Epidemiology and Biostatistics, McGill University Faculty of Medicine, Montreal, Quebec, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Gray-Donald
authors.forename: M S
authors.initials: MS
authors.lastname: Kramer
mesh_terms: D004812:Epidemiologic Methods; D006801:Humans; D011897:Random Allocation