TUTORIAL

Question 1

what is sampling?

Answer 1

a small number of observations

Question 2

what does p<0.05 mean?

Answer 2

there is a statistically significant difference, so the null hypothesis is rejected

Question 3

what is relative risk and what does it tell us?

Answer 3

incidence in exposed/incidence in unexposed

value greater than 1= the factor does increase the risk

Question 4

what is attributable risk?

Answer 4

incidence in exposed - incidence in unexposed

Question 5

when is it possible to calculate the odds ratio?

Answer 5

Case control as incidence is known

Question 6

how do you calculate the odds ratio?

Answer 6

ODDS OF EXPOSURE!!

odds of exposure in the diseased group/odds of exposure in the disease free group

Question 7

what does the odds ratio tell us?

Answer 7

greater than 1 = exposure is more likely in group of cases than exposed
less than 1 = more likely in control than the cases

Question 8

how do you deal with confounding?

Answer 8

stratification = when analysing risks for each factor are calculated separately 
standardisation = during analysis
regression = analysis, use a statistical model