1. What is Relative Risk?

Relative Risk (RR) is a measure of the strength of association between an exposure and an outcome. It compares the probability of an event occurring in an exposed group versus an unexposed group.

2. How Does the Calculator Work?

The calculator uses the Relative Risk formula:

Where:

• \( Incidence_{Exposed} \) — Incidence rate in the exposed group (proportion)
• \( Incidence_{Unexposed} \) — Incidence rate in the unexposed group (proportion)

Explanation: The relative risk indicates how many times more likely the outcome is in the exposed group compared to the unexposed group.

3. Importance of Relative Risk Calculation

Details: Relative Risk is crucial in epidemiological studies for assessing the relationship between risk factors and health outcomes, helping to determine causal associations and guide public health interventions.

4. Using the Calculator

Tips: Enter incidence rates as proportions (values between 0 and 1). Both values must be valid (incidence unexposed must be greater than 0).

5. Frequently Asked Questions (FAQ)

Q1: What does a Relative Risk of 1 mean?
A: A RR of 1 indicates no association between exposure and outcome - the risk is the same in both groups.

Q2: What is considered a significant Relative Risk?
A: Typically, RR values significantly different from 1 (usually with 95% confidence intervals not including 1) are considered statistically significant.

Q3: How is Relative Risk different from Odds Ratio?
A: RR compares probabilities directly, while OR compares odds. RR is more intuitive but requires cohort studies, while OR can be used in case-control studies.

Q4: When should Relative Risk be used?
A: RR is ideal for cohort studies and clinical trials where true incidence rates can be calculated for both exposed and unexposed groups.

Q5: What are the limitations of Relative Risk?
A: RR can be misleading when baseline risks are very low or very high, and it doesn't account for confounding factors without proper study design.