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#1
03-28-2015
 USMLE Forums Scout Steps History: CS Only Posts: 48 Threads: 33 Thanked 2 Times in 2 Posts Reputation: 12
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??!

#2
03-29-2015
 USMLE Forums Addict Steps History: CK Only Posts: 143 Threads: 18 Thanked 78 Times in 62 Posts Reputation: 88

I've always used the ad/bc and it's been working magic for me
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#3
03-30-2015
 USMLE Forums Newbie Steps History: Not yet Posts: 8 Threads: 3 Thanked 1 Time in 1 Post Reputation: 11

ALL are same and result as ad/bc...

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