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Journal Article CAUSALITY INFERENCE IN OBSERVATIONAL VS. EXPERIMENTAL STUDIES: AN EMPIRICAL COMPARISON Get access KATHERINE GRAY-DONALD, KATHERINE GRAY-DONALD 1Department of Epidemiology and Biostatistics, McGill University Faculty of MedicineMontreal, Quebec, Canada Reprint requests to Dr. K. Gray-Donald, Department of Epidemiology and Biostatistics, McGill University, 1020 Pine Avenue West, Montreal, PQ, Canada H3A 1A2 Search for other works by this author on: Oxford Academic PubMed Google Scholar MICHAEL S. KRAMER MICHAEL S. KRAMER 2Departments of Pediatrics and of Epidemiology and Biostatistics, McGill University Faculty of MedicineMontreal, Quebec, Canada Search for other works by this author on: Oxford Academic PubMed Google Scholar American Journal of Epidemiology, Volume 127, Issue 5, May 1988, Pages 885–892, https://doi.org/10.1093/oxfordjournals.aje.a114891 Published: 01 May 1988
Gray‐Donald et al. (Sun,) studied this question.