Module 5: Risk Factors

risk

probability that harm will occur

• calculate the incidence rate

cohort study design

compares exposed & not exposed groups

• participants selected on exposure status, not outcome

• followed over time to see who develops outcome

• start with healthy people

relative risk

[incidence rate in exposed]/[incidence rate in non-exposed]

case-control study design

start by identifying cases, then find healthy controls

• compares past exposures in cases & controls (retrospective)

odds ratio

[odds of exposure in cases]/[odds of exposure in controls]

concurrent

at the same time

intention to treat

analyzing participants in the groups to which they were originally randomized, regardless of whether they adhered to assigned treatment

prognostic factor

characteristic that is strongly associated with an outcome

quasi-experimental design

subjects are not randomly assigned to treatments

protective factor

decreases the likelihood of a negative health outcome