Relative Risk (Risk Ratio) in Medical Statistics

In medical statistics, relative risk (RR) is a measure of the strength of the association between an exposure and an outcome. It is defined as the ratio of the probability of an outcome occurring in the exposed group to the probability of the outcome occurring in the unexposed group. A higher RR indicates a stronger association between the exposure and the outcome.It's particularly common in cohort studies and randomized controlled trials.

Understanding Relative Risk

1. Definition: The Relative Risk is a ratio of the probability of the event occurring in the exposed group versus the unexposed (or control) group. It's a measure of the strength of the association between an exposure and an outcome.

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3. Formula: The RR is calculated using the following formula:

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   $\text{RR}=\frac{\text{Incidence in the Exposed Group}}{\text{Incidence in the Unexposed Group}}$

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   Where incidence refers to the proportion of individuals who develop the condition over a specified period.

How to calculate relative risk (RR) in steps:

Step 1: Set up your 2x2 table:

A 2x2 table is a simple table that summarizes the data from your study. It has two rows (exposed and unexposed) and two columns (disease present and disease absent). Enter your data into the table...