Composite Endpoints: Sometimes More than a Solely Economic Consideration
American Journal of Clinical and Experimental Medicine
Volume 1, Issue 1, July 2013, Pages: 24-34
Received: Jun. 18, 2013; Published: Jul. 20, 2013
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Charles J Kowalski, University of Michigan, Ann Arbor MI 48109 USA
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Endpoints are response variables, or outcomes, that are measured during the course of a clinical trial. I consider endpoints that are either events (e.g., death) or the time to an occurrence of an event (e.g., time to disease progression). A composite endpoint (CEP) is an endpoint that consists of a number of component endpoints, and is considered to have occurred as soon as any one of its components occurs. For example if CEP = death + disease progression, the CEP is said to have occurred as soon as either the disease progresses or the patient dies. It is seen that one of the results of using a CEP is to increase the event rate; and this in turn can reduce the sample size or the time required to observe a specified number of events, thereby resulting in a speedier, less costly clinical trial. Many believe that the only reason CEPs are ever employed is to this end, viz., saving money. I argue that there may be other circumstances that suggest the use of CEPs – that the choice of the primary response variable should be driven by the question the trial is being designed to answer.
Clinical Trials, Outcome Variables, Event Rates, Win Ratio, Quality of Life
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Charles J Kowalski, Composite Endpoints: Sometimes More than a Solely Economic Consideration, American Journal of Clinical and Experimental Medicine. Vol. 1, No. 1, 2013, pp. 24-34. doi: 10.11648/j.ajcem.20130101.15
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