Analysis of cohort studies

Information from a cohort study can be displayed in a 2 x 2 table, see Table a.

The data in Table a has been taken from a hypothetical cohort study to investigate the association between smoking and cancer.

The relative risk (RR) is a measure of association for a cohort study.

It tells us how much more likely (or less likely) it is for people exposed to a factor to develop a disease compared to people not exposed to the factor.

As revision look at the RLO on how to calculate Risk.

The relative risk (RR) is the ratio of the attack rates of a disease (cancer in this case) among people exposed to the factor (smoking) and those not exposed to the factor (smoking).