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Old 08-21-2012
tyagee's Avatar
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Stats Which study design to choose? and Why?

A group of researchers wants to investigate an outbreak of acute diarrhea that occurred in a small coastal town.
About 50 people developed severe hemorrhagic diarrhea and one fatal case was reported. The researchers believe
that the outbreak is related to the seafood prepared at one of the coastal restaurant. Which of the following study
designs is most appropriate to investigate the hypothesis?

A) Cohort study
B) Cross-sectional study
C) Case-control study
D) Ecologic study
E) Clinical trial

**i am choosing cross sectional study because i think i need to get
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Old 08-21-2012
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i will choose C..case control study;
the pxts where exposed in the past to an insult which they believe is the cause of the diarrhea.
its a retrospective and observational study so i think "C" suits most
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Old 08-21-2012
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I will also go with C .

Compare grp of ppl w dx to a grp without.
Looks for Prior exposure or risk factor.
Asks " What Happened". ( FA 2011)


?????????????
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Old 08-21-2012
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A retrospective cohort study is the best possible study in this case, considering its a small town. A list of people who ate at this restaurant wouldn't be very hard to obtain.

http://www.cdc.gov/excite/pdf/food_poisona.pdf
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Old 08-21-2012
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Quote:
Originally Posted by tyagee View Post

**i am choosing cross sectional study because i think i need to get
C) Case-control study

the researchers are looking for a causal relationship. cross-sectional study doesn't provide that.
The best study for causal relationship is a cohort study, then case-control study. I agree that retrospective cohort study would be the best but we don't have it in the given options (I assume that when they say just 'cohort study' they mean classic definition which refers to a prospective type of study). Since they are looking for a retrospective study I'll go with case-control
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Old 08-21-2012
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Quote:
Originally Posted by Casandra View Post
C) Case-control study

the researchers are looking for a causal relationship. cross-sectional study doesn't provide that.
The best study for causal relationship is a cohort study, then case-control study. I agree that retrospective cohort study would be the best but we don't have it in the given options (I assume that when they say just 'cohort study' they mean classic definition which refers to a prospective type of study). Since they are looking for a retrospective study I'll go with case-control
Great...Which school did you go to?
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Old 08-21-2012
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Retrospective study- case control


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Quote:
Originally Posted by Doc4Step1 View Post
Great...Which school did you go to?
why?......
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Quote:
Originally Posted by Casandra View Post
why?......
Cos I find your explanations better than most of the Qbanks.
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Old 08-22-2012
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Quote:
Originally Posted by Casandra View Post
C) Case-control study

the researchers are looking for a causal relationship. cross-sectional study doesn't provide that.
The best study for causal relationship is a cohort study, then case-control study. I agree that retrospective cohort study would be the best but we don't have it in the given options (I assume that when they say just 'cohort study' they mean classic definition which refers to a prospective type of study). Since they are looking for a retrospective study I'll go with case-control
what do you mean by this ?

The best study for causal relationship is a cohort study
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