The value of observational studies in eye care today

Published:August 13, 2021DOI:
      Health care professionals are taught that the “gold standard” evidence to guide clinical decisions is the randomized clinical trial (RCT). Although I take no issue with the statement, it ignores the foundational role of observational studies to provide background information to characterize diseases. This information is essential to design a robust RCT. RCTs can demonstrate many things: whether treatments work to manage or cure diseases, which type of patient is best suited for the treatment, what side effects can be expected, and the proper dosage of a drug or design of a device, to name a few. But, in my years as a clinical researcher designing RCTs, I’ve come to appreciate the value, and scarcity of observational studies that simply describe conditions or clinical measurements in populations without any intervention being applied. Studies that allow us to understand the eye without the constraints RCTs (such as narrow subject eligibility guidelines, bias toward more educated subjects, etc).


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