Randomised Trials and Other Evidence Flashcards Preview

Year 3: CSP & PH > Randomised Trials and Other Evidence > Flashcards

Flashcards in Randomised Trials and Other Evidence Deck (10)
1

What are 'parallel groups' when used in randomised trials?

when the effect of a treatment is curative (non-reversible)

2

What are 'cross-over groups' when used in randomised trials?

when the treatment effect is reversible

3

What are the advantages of cross-over trials vs parallel groups trials?

• Fewer participants needed
• Allows qualitative data to be sued to avoid ‘scores’ or quantifying subjective symptoms
• Compares 2 drugs in the same individual rather than one drug in two different people
• Can omit non-compliers in the analysis as the participant is their own control

4

What is an interventional study design?

parallel or cross-over randomised trial

5

What is an observational study design?

cohort (prospective) or case control (retrospective study)

6

What are the pros and cons of cohort studies?

• Rigorous
• Long duration
• Large size required
• Susceptible to confounders

7

What are the pros and cons of case-control studies?

• Quick
• Small numbers needed
• Susceptible to bias – especially recall bias
• Susceptible to confounders

8

What is an odds ratio?

The odds of an event to the odds of the non-event

9

What is 'relative risk'?

The risk of an event happening against the whole group

10

What's the difference between an odds ratio and a relative risk?

• Odds ratio – the odds of an event to the odds of the non-event
• Relative risk – the risk of an event happening against the whole group