epidemiology

Question 1

the 4 steps of evidence based medicine

Answer 1

1. formulate an answerable Q
2. track down the best evidence
3. critically appraise the evidence (find out how good)
4. apply the evidence

Question 2

what does PICO stand for

Answer 2

Population/patients
Intervention (exposure, test)
Comparison/control
Outcome (incl. time if relevant)

Question 3

appraisal of any study must consider

Answer 3

internal validity
results
applicability

Question 4

two types of validity

Answer 4

internal - are the results correct for the people in the sample?
external - if so, does the sample fairly represent the kind of patients in my practice?

Question 5

threats to internal validity

Answer 5

bias (systematic error)
confounding (3rd factor)
chance (random error)

Question 6

criteria for a confounder

Answer 6

1. associated with exposure
2. associated with disease (risk factor)
3. not part of the causal chain from exposure to disease