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Old 10-02-2011
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Stats Case control study can't determine prevalence!

Why can't case control study study assess prevalence of a disease but a cross sectional study can
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Old 10-02-2011
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Because in case control study you are studying only two groups.

In order to determine the prevalence you need to study the whole population or at least a representative sample of the population.

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Old 10-04-2011
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Quote:
Originally Posted by Shahzaib View Post
Why can't case control study study assess prevalence of a disease but a cross sectional study can
Well, the problem with a case control study is that you are setting the margins in the 2 by 2 table ...you're deciding how many cases and controls you want to have in your study... thus, the calculation of incidence / prevalence in this scenario would be biased.
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Old 05-05-2013
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Default prevalence in case control studies

I think it is not possible to get prevalence of outcome from case control studies. However, could we get the prevalence of exposure ( smoking for example for cancer lung) among both cases and control
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Old 05-06-2013
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because there is no appropriate denominator in case control study...
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