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Old 12-04-2010
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Stats Positive Predictive Value Versus Sensitivity

What situations would it be best to use ppv? what situations would it be better to use sensitivity as a measurement value? Arent't they both relatively similar to one another
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Old 12-04-2010
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Arrow Here's the difference

You test your patient and you found him HIV positive. He comes and asks you what are the chances that the test is correct, you then tell him the PPV rate of the test. You can't tell him the sensitivity.

So PPV is a post test probability. The probability that you truly have the disease when the test is positive.

While sensitivity is a pre test probability. It's how good the test in ruling out people with the disease (less false negatives).
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