Population Health

Question 1

Formula for Sensitivity (and define) of A diagnostic test from 2x2 table?

Answer 1

Sensitivity = True Positive / (True Positive + False Negative). % of people WITH disease the WILL test POSITIVE

Question 2

Formula for Specificity (and define) of a diagnostic test from 2x2 table?

Answer 2

Specificity = True Negatives / (True Negatives + False Positives). % of people WITHOUT the disease the WILL test NEGATIVE.

Question 3

Formula for Positive predictive value (PPV) (and define) of a diagnostic test from 2x2 table?

Answer 3

Positive predictive value (PPV) = True Positives / (True Positives + False Positives). % of positive tests that are truly positive.

Question 4

Formula for Negative predictive value (NPV) (and define) of a diagnostic test from 2x2 table?

Answer 4

Negative predictive value (NPV) = True Negatives/(True Negatives + False Negatives). % of negative tests that are negative positive.

Question 5

Do Negative predictive value and Positive predictive value have a positive or negative correlation with underlying disease prevalence

Answer 5

NPV = negative correlation
PPV = positive correlation