Pharm: Benefit vs. Risk of Drug Therapy

Question 1

According to studies discussed, do physicians and other healthcare professionals use evidence-based medicine effectively?

Answer 1

Unfortunately, no. Physicians fall victim to the same reporting tricks that make patients view outcome measures differently.

Question 2

What is EER?

Answer 2

experimental event rate; the rate at which the experimental agent or variable has an outcome effect

Question 3

What is CER?

Answer 3

control (or comparison) event rate; the rate at which the outcome occurs in the control group

Question 4

What is relative risk?

Answer 4

the probability of the outcome in treated patients relative to the probability of the outcome in untreated patients

Question 5

How is relative risk calculated?

Answer 5

RR = EER / CER

Question 6

What is the relative risk ratio?

Answer 6

the difference in proportions of untreated and treated patients who experience a particular outcome relative to the proportion of untreated patients who would experience the outcome

Question 7

How is the relative risk ratio calculated?

Answer 7

RRR = (CER – EER) / CER

Question 8

True or false: the relative risk ratio tends to hide small differences in effect.

Answer 8

False - it tends to exaggerate small differences. For example: say a drug reduces the rate of death in a sick patient population. Placebo group sees 10% death while drug group sees 8% death. The RR is 2% different but the RRR is 20% less in the drug group; makes a small difference (2%) look bigger/exaggerated (20%).

Question 9

What is absolute risk?

Answer 9

the absolute difference in the proportion of treated and untreated patients who experience an outcome

Question 10

Absolute risk can have 2 forms, depending on whether risk goes up or down. What are they called?

Answer 10

Absolute risk reduction

Absolute risk increase

Question 11

Which method of reporting risk is the most straightforward?

Answer 11

Absolute risk

Question 12

How is the absolute risk calculated?

Answer 12

ARR = CER – EER

Question 13

What is the NNT?

Answer 13

Number Needed to Treat; this number is the number of people needed to undergo treatment before one person will experience benefit; another way of reporting an outcome, ex: if the absolute risk reduction is 2%, the NNT is 50 because 2 are benefitted per every 100 treated

Question 14

How is NNT calculated?

Answer 14

NNT = 100 / ARR

Question 15

What is the number needed to harm?

Answer 15

the complement to NNT when examining the number of patients who will be treated before a patient experiences harm from the treatment; this can be lower than the NNT and is important to consider when evaluating risk/benefit

Question 16

What is meant by an evidence-based approach to therapeutics?

Answer 16

this would be accurately considering the risk/benefit ratios, and not being afraid to admit that a treatment might not actually have any more benefit than doing nothing - because people are actually designed to heal themselves – mind blown