Exam Two - RCT Part One

Question 1

RCTs are the gold standard for…

Answer 1

showing cause and effect

Question 2

RCTs typically have high _________ validity

Answer 2

internal

Question 3

what are 3 things we should consider in order to be critical consumers of RCTs?

Answer 3

1 - importance/clinical relevance (size of effect)
2 - generalizability
3 - internal validity (PEDro)

Question 4

What levels of evidence are RCTs?

Answer 4

1b or 2b

Question 5

t or f, authors are always truthful and transparent when reporting research findings

Answer 5

false, they can fudge details and exaggerate results to bias readers
(trial design, conduct, analysis/interpretation)

Question 6

what was the goal of the CONSORT statement

Answer 6

CONsolidated Standards of Reporting Trials
- increase transparency of important aspects of the trail (so reader can interpret internal validity for themselves)

Question 7

What is the purpose of the flow diagram

Answer 7

depict the passage of participants through a RCT (did any people drop out, if so, why?)

Question 8

What are the 4 stages of an RCT where you have to report sample size

Answer 8

1 - enrollment
2 - allocation
3 - follow-up
4 - analysis

Question 9

what are the two questions you must answer at each stage about sample size?

Answer 9

1 - number of participants for each group
2 - reason for loss or removal

Question 10

what are some common explanations for loss of subject data

Answer 10

• drop outs during intervention
• refusal of assigned treatment
• lack of compliance

Question 11

why is missing data a big deal?

Answer 11

threatens internal validity

Question 12

what are two common ways to handle missing data for analysis

Answer 12

1 - completer analysis
2 - intention to treat analysis

Question 13

completer analysis

Answer 13

• exclude missing data
• analyze ONLY the results of subjects who complied with the study protocol

Question 14

intention to treat analysis

Answer 14

• include missing data
• data analyzed according to the initial random assignments regardless of the treatment they actually received

Question 15

pros of completer analysis

Answer 15

• demonstrates the effect of a treatment if the patient is compliance

Question 16

cons of complete analysis

Answer 16

disregards the results of patients who dropout
- sub. perceive gain will probs stay and those that don’t will probs leave
unequal group numbers at the end of the study
- increase likelihood of certain stats assumptions being violated

Question 17

completer analysis use may be justified if….

Answer 17

the number of missing cases is small and RANDOM cases are missing

Question 18

“last observation carried forward” means…

Answer 18

the last know data point is used for the final outcome for the subject (used in ITT analysis)

Question 19

ITT analysis protects….

Answer 19

sample size calculation and similar group sizes

Question 20

T or F, if you use completer analysis you’ll get a PEDro point

Answer 20

false, you will get a point if you use ITT analysis

Question 21

How is ITT analysis considered to reflect clinical practice

Answer 21

• some patients are noncompliant
• answers “how will this treatment work for me if it is applied in a similar clinical environment”

Question 22

ITT analysis is believed to guard against the potential for bias if…

Answer 22

dropouts are related to outcomes or group assignment

Question 23

ITT analysis may bias the results towards an effect if:

Answer 23

many people dropout from the control group but their treatment IS effective

Question 24

ITT analysis may bias the results toward no effect if:

Answer 24

many people dropout from the treatment group but their treatment IS effective

Question 25

Why do most current recommendations say use ITT analysis not completer?

Answer 25

because is more closely resembles clinical practice

Question 26

Many papers report ____ completer and ITT analysis

Answer 26

both
Dr. WIllson thinks this is BEST research practice