Equations

Question 1

Sensitivity

Answer 1

ability to find true positives
SnNout
Positive overlap/ total positives according to gold standard

Question 2

Specificity

Answer 2

ability to find true negatives
SpPin
negative overlap/ total negatives according to gold standard

Question 3

PPV

Answer 3

positive predictive value

actual positive tests / total positives the test found

Question 4

NPV

Answer 4

negative predictive Value

actual negative tests/ total negatives the test found

Question 5

LR +

Answer 5

sensitivity/ (1-specificity)

Question 6

LR -

Answer 6

(1-sensitivity) / specificity

Question 7

Pretest Odds

Answer 7

prevalence/ (1-prevalence)

Question 8

Posttest Odds

Answer 8

\+ = LR + x pretest odds
- = LR- x pretest odds

Question 9

Standardized Effect side

Answer 9

mean 1 group - mean group 2 / pooled SD
.2 minimal effect size
.5 moderate effect size
.8 large effect size

Question 10

Relative Risk Reduction (RRR)

Answer 10

by how much does the program reduce the risk?

= (CER - EER)/CER*100

Question 11

CER

Answer 11

control event rate

Question 12

EER

Answer 12

experiment event rate

Question 13

ARR - Absolute Risk Reduction

Answer 13

CER - EER

if high then the program reduces the risk

Question 14

NNT

Answer 14

number needed to treat; want it to be low; 1

1/ARR or 1/ABI

Question 15

Absolute Benefit Increase - ABI

Answer 15

EER - CER

Question 16

Relative Benefit Increase - RBI

Answer 16

(EER - CER)/ CER *100