Role of observational studies versus clinical trials in ESRD research

Abstract

Randomized controlled clinical trials have been considered by many to be the only reliable source for information in health services research. This review considers the advantages and limitations of observational studies as compared to randomized clinical trials. It presents specific examples of scientific research done with observational registry data to show that some research is more feasible with an observational approach and that this approach may lead to better designs of prospective clinical trials. Such trials continue to be the gold standard in outcomes research. © 2000 by the International Society of Nephrology.