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Old 12-01-2011
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Stats Incidence and prevalence Question

1000 patients are enrolled from a community with recurrent HSV infections and are randomized: 500 recieve the new drug and 55 recieve the placebo. The results are that the average duration of recurrent HSV outbreaks in the new drug group is 1 week, compared with 2 weeks in the placebo group. Which of the following outcomes regarding symptomatic HSV infections is most likely in the greater population if all affected patients in the community are treated with the new drug?
a) incidence will decrease by half
b) incidence will double
c) prevalence will decrease
d) prevalence will double

At first i thought it was b because each week the patients are getting reinfected again but then i thought since they were getting reinfected it means they are not new cases? or are they? so that cancels out incidence (answer b) so does this mean it's prevalence which is answer d?

I got answer a wrong

thanks so much
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Old 12-01-2011
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1000 patients are enrolled from a community with recurrent HSV infections and are randomized: 500 recieve the new drug and 55 recieve the placebo. The results are that the average duration of recurrent HSV outbreaks in the new drug group is 1 week, compared with 2 weeks in the placebo group. Which of the following outcomes regarding symptomatic HSV infections is most likely in the greater population if all affected patients in the community are treated with the new drug?
a) incidence will decrease by half
b) incidence will double
c) prevalence will decrease
d) prevalence will double


is the answer A?
incidence are NEW cases for a given time.
Prevalance on the other hand is cases already present.

if I were treating all affected with the new drug - those are the prevelant population- so if I try to prevent new outbreaks ( that is symptomatic ) I would be decreaseing the incidence.

Am I correct?
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Old 12-01-2011
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The answer is not a as I originally put A but it was marked wrong
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I cry the Answer is C
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Old 12-01-2011
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Average duration is decreased from 2 week to 1 week ..it means that prevalence is decreased..
So answer is C
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C . .. . ......
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Old 12-01-2011
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source of question?
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Old 12-02-2011
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Is it prevalence because the patients are getting reinfected? So then the reinfected doesn't count for the the new cases
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