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Updated: Jul 14, 2026

Transcutaneous Assessment of Renal Function in Conscious Rodents
Published on: March 26, 2016
The valuable contribution of observational studies to nephrology
K J Jager1, V S Stel, C Wanner
1ERA-EDTA Registry, Department of Medical Informatics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. k.j.jager@amc.uva.nl
Abstract:
In studies on the effects of therapy (or other interventions), the randomized controlled trial (RCT) is an almost unbeatable standard in clinical research. The value of RCTs leaves unabated the valuable contributions of observational studies to medicine. This paper discusses some limitations of RCTs providing examples where these are not possible, inappropriate, inadequate, or unnecessary. Thereafter, it focuses on observational studies and gives a number of examples of studies on etiology, diagnosis, prognosis, and adverse effects, where observational designs have provided answers to research questions that could not have been answered by RCTs. Strengths and weaknesses of the different observational study designs are discussed. Finally, it is concluded that both observational studies and RCTs fulfill a complementary and valuable role in nephrology.
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