(2) Evidence-Based Medicine

Question 1

Relative Risk Reduction Calculation

Answer 1

RRR= (CER-EER)/CER

=ARR/CER

Question 2

Absolute Risk Reduction Definition

Answer 2

Difference between patients taking the drug vs. placebo

Question 3

Absolute Risk Reduction Calculation

Answer 3

ARR=CER - EER

= (control event rate)-(experimental event rate)

Question 4

Number needed to treat definition

Answer 4

of patients that have to take the drug for one person to be treated.
Degree of benefit or risk
Lower the number more clinically significant

Question 5

Number needed to treat calculation

Answer 5

NNT=100/ARR

=100/(CER-EER)

Question 6

Number needed to harm (NNH) definition

Answer 6

Number of patients who have to take the drug to have an adverse reaction

Question 7

Absolute risk increase calculation

Answer 7

ARI= EER - CER

Question 8

RRR vs. NNT

Answer 8

RRR- can’t discriminate large vs. small risk - good for marketing
NNT- better estimate of benefit or risk

Question 9

P value

Answer 9

probability observed result is due to chance

P

Question 10

Confidence Interval

Answer 10

range of plausible results (precision of results)