Positive predictive value is the probability that disease is present given a positive test.

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Positive predictive value is the probability that a disease is present when the test result is positive. It answers the question: among those who test positive, how many truly have the disease? Mathematically, PPV = true positives divided by all positive test results. This is different from sensitivity (how likely the test is to be positive if disease is present) and specificity (how likely the test is negative if disease is absent), and it’s also different from the negative predictive value (the probability of no disease given a negative test). The other options describe related ideas (the complement of PPV, or the probability of disease given a negative result, i.e., NPV) but do not reflect the meaning of PPV itself.