Epi module 6

Question 1

Sensitivity

Answer 1

TP/ TP+FN

Question 2

Specificity

Answer 2

TN/TN+FP

Question 3

PPV

Answer 3

chance that a person who tests positive is actually positiveTP/TP+FP

Question 4

TNPV

Answer 4

chance that a person who tests negative is actually negativeTN/TN+FN

Question 5

what happens to PPV as prevalence goes down

Answer 5

gets worse

Question 6

relationship between sensitivy and specificity to PPV and NPV

Answer 6

seNsitivity inversely associated with false Negative ratesPecificity inversely associated with false Positive rate

Question 7

what does a test need to rule out a diagnosis

Answer 7

sensitivity - SnNout - sensitive test plus negative result rules out

Question 8

what does a test need to rule in a diagnosis

Answer 8

specificity - SpPin - specific test plus positive result rules in