Observational versus randomised trial evidence

Comment

Martin Wiseman. Lancet. 2004.

. 2004;364(9436):755-6; author reply 756-7.

doi: 10.1016/S0140-6736(04)16927-4.

No abstract available

Comment on

Beyond randomised versus observational studies.
Concato J, Horwitz RI. Concato J, et al. Lancet. 2004 May 22;363(9422):1660-1. doi: 10.1016/S0140-6736(04)16285-5. Lancet. 2004. PMID: 15158623 No abstract available.
Those confounded vitamins: what can we learn from the differences between observational versus randomised trial evidence?
Lawlor DA, Davey Smith G, Kundu D, Bruckdorfer KR, Ebrahim S. Lawlor DA, et al. Lancet. 2004 May 22;363(9422):1724-7. doi: 10.1016/S0140-6736(04)16260-0. Lancet. 2004. PMID: 15158637 No abstract available.
When are observational studies as credible as randomised trials?
Vandenbroucke JP. Vandenbroucke JP. Lancet. 2004 May 22;363(9422):1728-31. doi: 10.1016/S0140-6736(04)16261-2. Lancet. 2004. PMID: 15158638 No abstract available.