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Old 03-09-2012
tyagee's Avatar
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Stats Specificity Sensitivity Question!

A diagnostic test has a sensitivity of 64% and a specificity of 99%.
Such a test would carry the risk of which kind of problem?
a. High relative risk
b. Low likelihood ratio
c. False negatives
d. False positives
e. Low power

please explain without using the formula of Sn.
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Old 03-09-2012
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is it C.......?
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Old 03-09-2012
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Sensitivity= TP/TP+FN = 64%

Spec= TN/TN+FP = 99%

Idealy you would want the ratio of 10/10+0.1 (which is 99%)

But 10/10+6 (will be around 62%)
this means that there is a high rate of False Negativites
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Old 03-09-2012
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Default C.

Sensitivity includes, i.e. picks up all the positives.
Specificity excludes, i.e. does not pick up the negatives.

The test in the question has low sensitivity, so it doesn't pick up all the positives and therefore is prone to false negatives.
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abeer (03-11-2012), tyagee (03-09-2012)



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Biostatistics-Epidemiology, Step-1-Questions

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