biostatistics & pharmacoeconomics

Question 1

RR equation

Answer 1

risk in tx group / risk in control group

Question 2

RR interpretation

Answer 2

RR >1 greater risk of outcome in tx
RR <1 lower risk
RR = 1 same risk

patients are AS LIKELY to have disease progression as placebo group

Question 3

RRR equation and interpretation

Answer 3

1 - RR
LESS LIKELY to have progression

Question 4

ARR equation and interpretation

Answer 4

(% risk in control) - (% risk in tx)
x out of every 100 patients benefit from treatment OR for every 100 patients, x fewer will have disease progression

Question 5

NNT and NNH equation

Answer 5

1 / ARR
ROUND UP for NNT
ROUND DOWN for NNH

Question 6

odds ratio equation

Answer 6

AD / BC

Question 7

hazard ratio equation

Answer 7

hazard rate in tx / hazard rate in control

Question 8

what is ratio data

Answer 8

continuous
0 = NONE

Question 9

what is interval data

Answer 9

continuous
0 does not = NONE

Question 10

what is nominal data

Answer 10

categorical/discrete
age, gender, mortality

Question 11

what is ordinal data

Answer 11

categorical/discrete
pain scale, NYHA class

Question 12

what type of data will have a gaussian distribution

Answer 12

large sample sets of continuous data

Question 13

examples of independent variables

Answer 13

drugs, doses, placebos, patients
anything changed by the researcher

Question 14

examples of dependent variables

Answer 14

HF progression, BP, mortality
the effect from the independent variable

Question 15

CI equation

Answer 15

CI = 1 - alpha

Question 16

how do you interpret confidence intervals

Answer 16

statistically significant if the CI range does not include or p value is < alpha

Question 17

how do you interpret confidence intervals for relative risk, odds ratio, hazard ratio

Answer 17

statistically significant if the CI range does not include 1

Question 18

type I error

Answer 18

false positive
null hypothesis was rejected in error

Question 19

type II error

Answer 19

false negative
null hypothesis was accepted when it should have been rejected

Question 20

what is the significance of study power

Answer 20

1 - Beta
the probability that a test will reject the null correctly (the power to avoid a type II error)

Question 21

types of tests for continuous data

Answer 21

one sample t test for 1 group
paired t test for before & after of 1 group
student t test for 2 groups
ANOVA for >3 groups

Question 22

types of tests for categorical data

Answer 22

chi squared test

Question 23

sensitivity equation and interpretation

Answer 23

A / A+C x 100
test is positive in x% of patients that have disease

Question 24

specificity equation and interpretation

Answer 24

D / B+D x 100
test is negative in x% of patients without disease

Question 25

case control study

Answer 25

compares patients with a disease to those without retrospective

Question 26

cohort study

Answer 26

compares outcomes of a group exposed and not exposed to treatment prospective or retrospective

Question 27

incremental cost effectiveness ratio equation

Answer 27

(C2 - C1) / (E2 - E1)

Question 28

cost minimization analysis

Answer 28

costs of each intervention are compared (two ACEi are considered equivalent, but the costs are different)

Question 29

cost benefit analysis

Answer 29

compares benefits and costs of an intervention

Question 30

cost effectiveness analysis

Answer 30

compares effects to costs

Question 31

cost utility analysis

Answer 31

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