Developing Critical Appraisal Skills (05/11/2021) Flashcards
What is critical appraisal?
- A systematic process of deciding if the available evidence is good enough to base practice on, or of determining the best available evidence.
Why do we use the CASP checklist?
Provide an organise and systematic approach which can be replicated between reviewers but also by the reader and to help make an overall assessment o the internal validity and the relevance of a study.
What does CASP stand for?
Critical appraisal skills programme
What does PICO stand for?
Population, intervention, control, outcome.
What is a limitation of poor randomisation methods?
Exaggerated treatment effects which are open to subversion by researchers or clinicians and have a knock-on effect on systematic reviews.
How Is randomisation mostly done in RCT?
Using a secure web based central randomisation device hosted by…
Describe stratified randomisation?
Designing randomisation to force balance between trial arms- used when you want to avoid chance imbalance in factors that you know are related to the outcome of interest.
Describe permuted blocks
-A methods of restricted randomisation whilst random can ensure equal number of participants in trial arms. The use of blocks can be problematic as it may allow the sequence to become predictable, so the sizes of the blocks can be varied.
What is a power calculation?
A power calculation is a way that the people doing the trial can decide how many people the trial should have In it. It’s a red flag when a trial has not had a power calculation.
5% significance level
Probability of rejective the null hypothesis if the null is true. This is the probability of falsely concluding an effect of a treatment on outcome X.
Power
The probability of rejecting the null hypothesis when it is false. The chance we accept there is no difference in treatment effects on outcome X when there is.
Minimally important clinical difference.
The difference in outcome X we expect to see between the treatment arms.