HTH 450- Sensitivity and Specificity
as prevalence increases, so does ___
PPV
measure of positive yield
PPV
specificity formula
TN/ TN + FP
sensitivity formula
TP/ TP + FN
formula for PPV
a/a+b
formula for NPV
d/d+c
higher sensitivity= fewer people are given ____ _____ results
false negative
NPV is affected by the number of _____ ____
false negatives
high specificity= fewer people are given _____ _____ results
false positive
of those who screen negative, how many are actually negative
negative predictive value (NPV)
of those who screen positive, how many are actually positive?
positive predictive value (PPV)
probability that a test correctly classifies as positive those who have preclinical disease
sensitivity
probability test correctly classifies individuals without preclinical disease as negative
specificity