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. 1996 May 11;312(7040):1215–1218. doi: 10.1136/bmj.312.7040.1215

Why we need observational studies to evaluate the effectiveness of health care.

N Black 1
PMCID: PMC2350940  PMID: 8634569

Abstract

The view is widely held that experimental methods (randomised controlled trials) are the "gold standard" for evaluation and that observational methods (cohort and case control studies) have little or no value. This ignores the limitations of randomised trials, which may prove unnecessary, inappropriate, impossible, or inadequate. Many of the problems of conducting randomised trials could often, in theory, be overcome, but the practical implications for researchers and funding bodies mean that this is often not possible. The false conflict between those who advocate randomised trials in all situations and those who believe observational data provide sufficient evidence needs to be replaced with mutual recognition of the complementary roles of the two approaches. Researchers should be united in their quest for scientific rigour in evaluation, regardless of the method used.

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These references are in PubMed. This may not be the complete list of references from this article.

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