Glossary - Research Basics and Terminology

• Chance of an event occurring; this is calculated by taking the number of individuals in the sample who experience the event divided by the number of individuals for whom the event did not occur
• Mainly used in case-control studies
• Small risk → Odds Ratio ~ Relative Risk
• Ranges:

1. 1. OR> 1.0 – exposure may increase the odds of a disease
   2. OR> 1.0 – exposure does not affect the odds of outcome
   3. OR< 1.0 – exposure may decrease the odds of a disease

• Example: OR= 3.7 for likelihood to die from a new antihypertensive drug as compared to an existing drug

→ Patients who received the new antihypertensive drug die 3.7 times more often than patients who received an existing drug.

→ The odds to die with the new antihypertensive drug is 3.7 times higher than with the existing drug.

Further information: Explaining Odds Ratios