Appendicitis

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Appendicitis

by gmat740 » Wed Jul 29, 2009 8:40 pm
Appendicitis (inflammation of the appendix) is potentially fatal; consequently, patients with symptoms strongly suggesting appendicitis almost have their appendix removed. The appropriate surgery is low-risk but performed unnecessarily in about 20 percent of all cases. A newly developed internal scan for appendicitis is highly accurate, producing two misdiagnoses for every 98 correct diagnoses. Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since .......

Which of the following logically completes the passage?

A. the patients who are correctly diagnosed with this test as not having appendicitis invariably have medical conditions that are much less serious than appendicitis
B. the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it
C. all of the patients who are diagnosed with this test as having appendicitis do, in fact,have appendicitis
D. every patient who is diagnosed with this test as having appendicitis has more than one of the symptoms generally associated with appendicitis
E. the only patients who are misdiagnosed using this test are patients who lack one or more of the symptoms that are generally associated with appendicitis

OA-B
Last edited by gmat740 on Thu Jul 30, 2009 2:52 am, edited 1 time in total.

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by madhur_ahuja » Wed Jul 29, 2009 10:34 pm
Its B ..

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by italian7745 » Thu Jul 30, 2009 1:04 am
IMO D

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by gmat740 » Thu Jul 30, 2009 1:19 am
madhur_ahuja wrote:Its B ..
Please give reasons.

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Re: Appendicitis

by nervesofsteel » Thu Jul 30, 2009 1:49 am
gmat740 wrote:Appendicitis (inflammation of the appendix) is potentially fatal; consequently, patients with symptoms strongly suggesting appendicitis almost have their appendix removed. The appropriate surgery is low-risk but performed unnecessarily in about 20 percent of all cases. A newly developed internal scan for appendicitis is highly accurate, producing two misdiagnoses for every 98 correct diagnoses. Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since .......

Which of the following logically completes the passage?

A. the patients who are correctly diagnosed with this test as not having appendicitis invariably have medical conditions that are much less serious than appendicitis
B. the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it
C. all of the patients who are diagnosed with this test as having appendicitis do, in fact,have appendicitis
D. every patient who is diagnosed with this test as having appendicitis has more than one of the symptoms generally associated with appendicitis
E. the only patients who are misdiagnosed using this test are patients who lack one or more of the symptoms that are generally associated with appendicitis
if misdiagnoses are always instances where the appendicitis was not there then doctors will not miss the right cases... they may still perform certain unnecessary operations due to misdiagnosis but they will not miss the cases which were really suffering....

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by viju9162 » Thu Jul 30, 2009 2:44 am
ya i also feel its B
"Native of" is used for a individual while "Native to" is used for a large group

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by niraj_a » Thu Jul 30, 2009 2:41 pm
i chose C, between C and B. i thought that removing the appendix of a person who does not have the inflammation is a major misdiagnosis.

is OG / Gprep the source?

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by Spring2009 » Thu Jul 30, 2009 7:29 pm
niraj_a wrote:i chose C, between C and B. i thought that removing the appendix of a person who does not have the inflammation is a major misdiagnosis.
is OG / Gprep the source?
This is what B mentions.

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by kaulnikhil » Fri Jul 31, 2009 12:25 am
the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it


now look at this way
the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does, in fact, have it

option 1 says that doctors will perform some misdiagnosis. but they wont miss on any one who has it ...wont miss on necessary ones

now refer to second one means 2 say that doctors will perform some misdiagnosis but will miss on anyone who has it ..so they miss on necessary ones

now let us analyse C
all of the patients who are diagnosed with this test as having appendicitis do, in fact,have appendicitis

fine all patients diagnosed have appendicitics .. good ..but what about the remaining people they still might b wrongly diagnosed as in case 2

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by iamcste » Thu Mar 04, 2010 4:19 am
while B is correct, Can any one comment specifically why A, D and E are incorrect?

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by max37274 » Thu Mar 04, 2010 4:47 am
Please explain the meaning of "without, however, performing any fewer necessary ones than before, since ....... "

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by subgeeth » Thu Mar 04, 2010 11:58 am
can any one explain what does the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it means

I didnt understand this line

Does it mean misadiagnoses are giving correct results or wrong results am not clear with this line

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by gmatmachoman » Thu Mar 04, 2010 12:51 pm
gmat740 wrote:Appendicitis (inflammation of the appendix) is potentially fatal; consequently, patients with symptoms strongly suggesting appendicitis almost have their appendix removed. The appropriate surgery is low-risk but performed unnecessarily in about 20 percent of all cases. A newly developed internal scan for appendicitis is highly accurate, producing two misdiagnoses for every 98 correct diagnoses. Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since .......

Which of the following logically completes the passage?

A. the patients who are correctly diagnosed with this test as not having appendicitis invariably have medical conditions that are much less serious than appendicitis

B. the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it
C. all of the patients who are diagnosed with this test as having appendicitis do, in fact,have appendicitis
D. every patient who is diagnosed with this test as having appendicitis has more than one of the symptoms generally associated with appendicitis
E. the only patients who are misdiagnosed using this test are patients who lack one or more of the symptoms that are generally associated with appendicitis

OA-B
A newly developed internal scan for appendicitis is highly accurate, producing two misdiagnoses for every 98 correct diagnoses.

Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before,-------------

Accurate Diagnosis can be defined as :

Patient as the symptom and the test scan is able to rightly predict that symptom.

Patient does not have the symptom and the test scan is able to predict rightly that patient does NOT have the symptom.

Misdiagnosis is defined as:

Patient has the symptom and the TestScan is not able to predict it properly

OR

Patient doesnot have symptom but the testscan predicts that patient has Symptom.

Now the newTest Scan, produces two misdiagnoses for every 98 correct diagnoses. So it can be any of the 2 above said conditions.


Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before,------------------


How Doctors can avoid unnecessary operations???If the testscan results that shows symtoms for a person who does NOT really have any symptom (inflammation) then Doctor can avoid the unnecessary operation.

U can even try Negating B.

the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does NOT, in fact, have it

After Negation,

the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does in fact, have it...

If this is the case, the whole advantage of using the new test scan is useless!!

Agreed, It was not easy for me to explain the nuances of the Argument.

If not clear ,plz dont hesitate to raise the flag!

Adding on to that, this was Karan's post..So for tougher post u can always review his older posts.

For some great quality post u can refer Maihuna,DanaJ,Jogitech,Pandey_Vineet,Komal,Fibbonnaci ,Pheonix, and ofcourse mine too for voulmes of posts.

For replies needless to mention plz gothru Testluv and all experts posts.

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by ssgmatter » Fri Mar 19, 2010 9:04 pm
Thanks for the awesome explanations guys....

But i am still not able to understand the meaning of this line of the sentence in the arg that says

Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before

Please explain

Thanks a heap!

Regards,
Phil

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by kevincanspain » Sat Mar 20, 2010 12:54 pm
How could such a test lead doctors not to perform all the necessary operations? Only if such a test misdiagnosed genuine cases of appendicitis.
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