Randomized Controlled Trials Flashcards
What is a RCT?
Test whether an intervention works by comparing it to a control condition
Describe an RCT?
Population –> Study sample –> Randomized –> Intervention/control –> outcome
What is cluster randomized?
Where we take groupings of individuals and randomize them
What is a cross over RCT?
Where take start/stop treatment and give the randomized groups the opposite therapy
What is the importance of an RCT design?
The study must be designed before it is executed
Why is it important to make sure that study is designed before it begins?
Limits bias
What is important with an RCT design with respect to population?
Who we want to study and where do we get them from
What is the importance of inclusion/excuslion criteria
Helps with ensuring data points are similar
Can limite generalizability
What is the importance of sample size?
With respect to the power measurement. Where we want to have a balance of power.
If the Sample size is too low what occurs?
Underpowered and data is not as backed
What if the sample size is too high?
unnecessary exposure and more resource intensive
By increasing the sample size what are we decreasing?
Chance
With respect to the intervention what is an important point in all RCT studies?
It needs to be specific very specific
What is important with respect to the treatment of controls/comparison groups?
Must be treated exactly the same way as the intervention group- the only different that can be present is the intervention
What are the differences between hard endpoints vs surrogate endpoints
Hard endpoints a definitive things that occur such as death, MI, stroke
Where surrogate endpoints are like blood pressure where it can lead to it
What is the primary endpoint
Main result that is measured at the end of the study to seee the effect of the intervention
What is the secondary endpoint
Additional results of interest but not the main focus.
We should not interpret these as the study was not designed around them, hence future RCT could be directed towards validating this secondary endpoints that are observed
What is a composite endpoint?
A primary endpoint that contains several events (MACE)
What are the benefits of composite endpoints?
Less subjects needed
What are the disadvantages of composite endpoints
Hard to determine the true effect of the intervention on each of the event types
Look at specific results for breakdown
What does randomization help to minimize?
Confounding
What is the main point with randomization?
Randomization minimizes confounding
What is complete randomization?
No limitations just straight up randomization
Wont necessarily get equal numbers in each of the groupW
What is block randomization
Used to force balance in the number of subjects in each group
What is Stratified randomization?
Used to achieve similarities in certain baseline characterisitics
Stratify via age
Stratify via clinic
What is Intention to treat?
Analyzing the data for all patients and according to the group they were originally ranomzied to
What is “Per protocol”
analyzing data only from subjects who completed the study or followed protocol exactly
Why is intention to treat better?
Preserves the valye of randomization
Once randomized
ANALYZE
What is main point of incorporating blinding into a study?
Blinding reduces bias
