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Old 03-28-2015
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Default Odds ratio formula

Hi..I'm so confused abt the OR formula..

I know it's ultimately: OR = ad/bc

But some review books say:
OR = (a/b)/(c/d)

Whereas others say: OR = (a/c)/(b/d)

Which ones right??!
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Old 03-29-2015
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I've always used the ad/bc and it's been working magic for me
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Old 03-30-2015
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ALL are same and result as ad/bc...
similarly, (a/c)/(b/d)=(a/c)x(d/b)=ad/cb=ab/bc
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