What would definitely happen to the predictive value (PV and PV-) if this test were administered in a population with a disease prevalence of 1% instead of 30%? (Note that the sensitivity and specificity of the test remain the same.)
Added by Diego O.
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PPV = [sensitivity × prevalence] / [sensitivity × prevalence + (1 − specificity) × (1 − prevalence)] - Negative predictive value (NPV, PV−): probability that a person does not have the disease given a negative test. NPV = [specificity × (1 − prevalence)] / [(1 Show more…
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