Calculating recurrence rate?

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Lothric

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Hey,

Question: "A new drug ‘X’ is developed for endometrial cancer in postmenopausal women. A pharmaceutical company claims that drug X alone will decrease recurrence of endometrial cancer after surgical treatment by 50% compared to standard therapy alone. The recurrence rate with standard therapy is currently 12%.

Which of the following values represents the maximum incidence of recurrence acceptable for the subjects treated with the new drug plus standard therapy?

a, 12 %
b, 3 %
c, 6 %

How do you calculate the recurrence rate? I fking hate these type of questions.

In my ******* intuitive way of thinking I'd say take the standard drug and you'll get a recurrence rate of 12. Now substract that with the recurrence rate of 6. That would make the net recurrence 6 %.

But if you do the opposite, i.e. taking the new drug first, 6, and then subtracting you'll get -6... But then again, no risk can be negative so maybe I'm just supposed to + that and it'll be 6 anyway...?

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It's not clear what is meant by "acceptable," but I assume they mean a rate that would corroborate the company's claim. So if drug X improves the recurrence rate by 50% over standard therapy, the maximum acceptable recurrence rate would be 50% lower than with standard therapy...which is 50% of 12%, or 6%. I'm not sure where the adding or subtracting comes in.

In my reading this question is just asking "what is 50% of 12%?" There's no special calculating necessary.

P.S. Usually when I hear "calculate recurrence rate" it's in reference to the recurrence of a genetic disorder in subsequent siblings of children who are affected, e.g. the rate of recurrence of CF in a family with an affected child. This does require at least some knowledge of how to calculate a conceptual entity, not just basic arithmetic.
 
It's not clear what is meant by "acceptable," but I assume they mean a rate that would corroborate the company's claim. So if drug X improves the recurrence rate by 50% over standard therapy, the maximum acceptable recurrence rate would be 50% lower than with standard therapy...which is 50% of 12%, or 6%. I'm not sure where the adding or subtracting comes in.

In my reading this question is just asking "what is 50% of 12%?" There's no special calculating necessary.

P.S. Usually when I hear "calculate recurrence rate" it's in reference to the recurrence of a genetic disorder in subsequent siblings of children who are affected, e.g. the rate of recurrence of CF in a family with an affected child. This does require at least some knowledge of how to calculate a conceptual entity, not just basic arithmetic.
Question asks not just recurrence rate with new drug (eg 50% drop), but rec. rate with new drug together with standard therapy - so a combo so to speak.
Not sure what calculating genetic probability of CF born children lol has to do with this.
 
Drug X decreases recurrence by 50% compared with standard therapy alone...standard therapy alone results in 12% recurrence. The combination is standard therapy (12%) plus drug X (50% decrease compared to standard). A 50% decrease compared to 12% is 6%. What am I missing?

Re: CF I mean that there is no algorithmic way one needs to learn to calculate "the recurrence rate" in "these types of questions" because it's basically defined in the question and isn't a separate concept unto itself. When I hear "calculate recurrence rate" I think of genetic scenarios, like CF, where the recurrence rate is a different concept that requires some sort of background knowledge.
 
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