








USMLE Step 1 Mnemonics Mnemonics, acronyms, reminders, and memorizing tips for the USMLE Step 1. 

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#1




Odds Ratio
The formula for odds ratio is easily remembered
The years can either be AD or BC AD = Anno Domini, After christ BC = Before Christ The odds ratio OD = AD/BC Of course remember that the A cell is always the disease with the risk and then simply cross to the D cell and divide by the other two cells. So for example in this 2X2 table The AD cells are in red and the BC cells are in yellow The A cell is the number of males with stroke. click image to enlarge Note in the case of Odds ratio we are measuring the likelihood that a stroke patient is being a male (risk factor) and not the reverse (we are not measuring the probability of getting a stroke if the patient is a male). 
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#2




Caution
I've seen an NBME question that requires the knowledge of this formula
A/C divided by B/D so the mnemonic of AD/BC is not always useful. 
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#3




Quote:
A/C divided by B/D = A/C times D/B = AD/BC I think your mnemonic is pretty good 
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#4




"Not in the case of Odds ratio we are measuring the likelihood that a stroke patient is being a male (risk factor) and not the reverse".
what do you mean by" not the reverse"?? 
#5




Quote:
While Relative Risk and Attibutable Risk: it starts with the risk factor and ends with the disease, i.e. if you are male then what's the likelihood you'll get stroke. 
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dr.tahaiqbal (12172013), life9 (04292011), madeha shahid (06092012), mayankkaushal (05232013), MSMZ (07142016) 
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BiostatisticsEpidemiology 
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