# Calculation of Odds Ratio (OR) / Relative Risk (RR)

Calculation of odds ratio/relative risk for the use of trimethoprim-sulfamethoxazole prophylaxis in cirrhosis:Adverse event occurs (infectious complication) |
Adverse event doesn't occur (no infectious complication) |
Totals | |
---|---|---|---|

Exposed to the treatment (experimental) |
1 a |
29 b |
30 a + b |

Not exposed to the treatment (control) |
9 c |
21 d |
30 c + d |

Totals | a + c 10 |
b + d 50 |
60 |