Public Health

Question 0

Specificity

Answer 0

Relates to a test’s ability to correctly identify negative results

True negatives / true negatives + false positives

True negatives / total well individuals

Question 1

Sensitivity

Answer 1

Proportion of true positives identified

true positives / (true positives +false negatives)

I.e. True positives/total sick individuals

Question 2

Positive predictive value

Answer 2

True positive / test outcome positive

Sensitivity x prevalence) / (sensitivity x prevalence) + (1-specificity)(1-prevalence

Question 3

Negative predictive value

Answer 3

True negatives / negative calls

Question 4

Hierarchy of evidence for interventions

Answer 4

Systematic reviews of RCTs
RCTs
Controlled trials
Cross sectional studies
Case reports and case series
Expert opinion