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Old 08-05-2012
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Stats Calculate the sensitivity from this 2X2 table

An experimental serologic test is developed to detect the presence of HIV antibody. Epidemiological analysis
reveals the results shown below.

People with HIV antibody People without HIV antibody
Positive test 100 50
Negative test 20 950

What is the sensitivity of this test?

A. 11%
B. 67%
C. 83%
D. 95%
E. 98%
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Old 08-06-2012
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Answer C.
83.

Code for this

SENSITIVE AC.
SPECIFIC BD.
Predicted---- AB,CD(+,-)

All denominators...

Last edited by cingulate.gyrus; 08-06-2012 at 10:14 AM. Reason: correction
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Old 08-06-2012
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Would be C
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answer is: (C). 83%

2X2 Statistics / Epidemiology Table (Punnett Square)
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C. 83%

Sensitivity = TP / TP + FN = 100 / 100 + 20 = 83.3%
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