Diagnostic Tests and Prognosis/Risk

Question 1

Definition of sensitivity

Answer 1

How well the test detects disease

Question 2

Sensitivity formula

Answer 2

True positive/(true positive + false negative)

Question 3

Definition of specificity

Answer 3

How well the test detects those without disease

Question 4

Specificity formula

Answer 4

True negatives/(true negatives + false positives)

Question 5

Likelihood ratio positive

Answer 5

Sensitivity/(1-Specificity)

Question 6

Positive predictive value

Answer 6

True positives/(true positives + false positives)

Question 7

Negative predictive value

Answer 7

True negatives/(true negatives + false negatives)

Question 8

Relative risk

Answer 8

(Event rate in intervention group)/(Event rate in control group)

Question 9

Relative risk reduction

Answer 9

1 - Relative risk

Question 10

Absolute risk reduction

Answer 10

(Event rate in intervention group) - (Event rate in control group)

Question 11

Number needed to treat

Answer 11

1/(Absolute risk reduction)

Question 12

Number needed to harm

Answer 12

1/(Absolute risk increase)

Question 13

Attributable risk

Answer 13

Difference in risk between exposed and unexposed groups

Question 14

Risk ratio

Answer 14

(Risk in exposed group)/(Risk in nonexposed group)

Question 15

Odds ratio

Answer 15

(Odds in exposed group)/(Odds in nonexposed group)