Lecture 6 - RCT

Question 1

What are the 3 reasons to conduct RCT?

Answer 1

evaluate new intervention before its given regulatory approval, evaluate controversial intervention, or to gain regulatory approval

Question 2

What is the first phase of an RCT

Answer 2

small study of 20-80 healthy volunteers who gets the drug

Question 3

what is the purpose of phase 1 of an rct

Answer 3

assess toxicity and pharmacological effects

Question 4

what is the second phase of an rct

Answer 4

study 100-200 diseased person and give them drug

Question 5

what is the purpose of phase 2 of an rct

Answer 5

assess safety and efficacy

Question 6

what is the third phase of an rct

Answer 6

RCT which is required for regulatory approval

Question 7

what is the purpose of phase 3 of an rct

Answer 7

assess effectiveness of new intervention compared to standard/placebo

Question 8

what is the fourth phase of an rct

Answer 8

follow up rct subjects past official end of RCT

Question 9

fourth phase of rct is classified as what study

Answer 9

observational study

Question 10

what is the purpose of phase 4 of an rct

Answer 10

assess rare side effects

Question 11

What is a single centred rct

Answer 11

patient recruited from same clinic/hospital

Question 12

what is a multi centred rct

Answer 12

patient recruited from diff clinic/hospital

Question 13

What are the three contributing factors of ___- that contribute to strength of RCT?

Answer 13

randomization ; 1. each subject has equal chance of being assigned to either group 2. equal # of ppl in each group 3. group subjects based on similar factors except intervention

Question 14

what is stratified randomization

Answer 14

divide pop into layers (stratum) by variable and randomize within each group

Question 15

What does stratified randomization do?

Answer 15

increases comparability btw two groups by focusing on one or more prognostic variable; ensures prognostic variables are equally distributed

Question 16

what is single blind

Answer 16

blind participants to eliminate participant bias

Question 17

what is double blind

Answer 17

blind data collectors/analysts to eliminate investigator bias

Question 18

what is triple blind

Answer 18

blind staff that administer treatment

Question 19

define washout period

Answer 19

time btw end of 1st intervention and start of 2nd must be long enough to wash out any carry over from 1 intervention (IN PLANNED CROSS OVER)

Question 20

define ordering effect

Answer 20

patients react differently to 1st intervention bc of psychological effects of being studied

Question 21

define factorial design

Answer 21

test 2 diff drugs on same pop; drugs have diff outcomes and independent modes of action

Question 22

how many groups are in a factorial design

Answer 22

4

Question 23

what are the cons of factorial design

Answer 23

might negatively impact compliance and recruitment

Question 24

what is intent to treat analysis

Answer 24

analyze patients according to original assignment

Question 25

define internal validity

Answer 25

degree to which a study provides an unbiased estimate of what it claims to measure ; conducted properly

Question 26

define external validity

Answer 26

results are generalizable

Question 27

RCTs assess what? therefore they have _____ valditiy

Answer 27

efficacy of intervention; internal validity

Question 28

what are cons of RCTs

Answer 28

subjects are atypical (good compliers, no comorbid disease)

Question 29

define clinical equipose

Answer 29

only expert medical community needs to be uncertain

Question 30

when cant you use an rct

Answer 30

chronic conditions, study rare side effects, randomization is unethical

Question 31

Observational studies arent ____ but assigned based on ________ wherease RCT participants are assigned based on _______

Answer 31

randomized, observation; randomization