Note 5 - Stats for Clinical Trials, Math 150 Jo Hardin Fall...

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Stats for Clinical Trials, Math 150 Jo Hardin Fall 2010 Retrospective versus Prospective Studies After much research (and asking many people who do not all agree!), I finally came across a definition of retrospective that I like. Note, however, that many many books define retrospective as synonymous with case-control. That is, they define a retrospective study to be one in which the observational units were chosen based on their status of the response variable. I disagree with that definition. As you see below, retrospective studies are defined based on the when the variables were measured . I’ve also given a quote from the Kuiper text where retrospective is defined as any study where historic data are collected (I like this definition less). Studies can be classified further as either prospective or retrospective. We define a prospective study as one in which exposure and covariate measurements are made before the cases of ill- ness occur. In a retrospective study these measurements are made after the cases have already occurred. .. Early writers referred to cohort studies as prospective studies and to case-control
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This note was uploaded on 02/17/2012 for the course MATH 151 taught by Professor Jo.h during the Fall '10 term at Pomona College.

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Note 5 - Stats for Clinical Trials, Math 150 Jo Hardin Fall...

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