Population Science Flashcards
What are inclusion and exclusion criteria?
Who should and shouldn’t take part in a trial.
What are outcome measures?
Agreed criteria for measurement and assessment of outcomes.
What do non-randomised trials lead to?
Selection bias
Known and unknown confounding factors.
What does blinding improve?
Removes selection bias.
What is a placebo?
An inert substance that is made to appear identical in every way to the active formulation with which it is compared.
What is an ‘as-treated’ trial?
Analyses only those who completed follow-up and complied with trial - loses the effects of randomisation as non-compliers as likely to be systematically different from compliers - leads to selection bias and confounding factors.
What is an ‘intention-to-treat’ trial?
Analyses everyone regardless of whether they completed follow-up or adhered to treatment, therefore preserves effects of randomisation, leading to minimal selection bias and confounders.
What is ‘loss to follow-up’?
When people drop out of the trial before it is complete - can be appropriate (their clinical condition requires them to drop out), or unfortunate (they choose to withdraw).
