What does a relative risk greater than 1 indicate in a cohort study?

• A. RR = risk in exposed / risk in unexposed.
• B. RR > 1 indicates higher risk with exposure.
• C. RR = 1 indicates no association.
• D. RR < 1 indicates a protective effect.

Answer: (B)

In a cohort study, relative risk shows how the risk of the outcome compares between people with the exposure and those without. It is computed as risk in the exposed group divided by risk in the unexposed group. When the relative risk is greater than 1, the exposed group has a higher risk of the outcome than the unexposed group, which means the exposure is associated with increased risk. This is the interpretation being tested. If the relative risk equals 1, there is no association; if it is less than 1, the exposure is associated with a lower risk, suggesting a protective effect. Remember that RR > 1 indicates association, not necessarily causation, and significance depends on whether the confidence interval excludes 1.