Disuss why we cannot calculate risk ratio for case-control study.

A study looking at urinary tract infection compared cases with non-cases and found that 65/100 cases had placement of indwelling bladder catheters compared 20/100 of non-cases.

1. Develop a table to display the data.

2. Calculate odds of exposure in cases and non-cases.

3. Calculate odds ratio.

4. Interprete odds ratio.

5. Disuss why we cannot calculate risk ratio for case-control study.