# Relative risk with 95% confidence intervals

## Relative risk is calculated in prospective studies

Relative risk with 95% confidence interval is the inferential statistic used in

If relative risk and the confidence interval

If relative risk and the confidence interval are both entirely

If relative risk and the confidence interval are both entirely

**prospective****and**__cohort____. With relative risk, the__**randomized controlled trials****width of the confidence interval**is the inference related to the**precision**of the treatment effect.If relative risk and the confidence interval

**crosses over 1.0**, meaning that the event is just as likely to occur as not occur, then researchers have a non-significant association between the variables.If relative risk and the confidence interval are both entirely

**above 1.0**, then people are**MORE AT RISK**of developing the outcome as a result of the treatment or exposure.If relative risk and the confidence interval are both entirely

**below 1.0**, then people are**LESS AT RISK**of developing the outcome as a result of treatment or exposure, denoting a "protective" effect.From a research design standpoint, the 2x2 table is used to find associations between an exposure and an outcome.

**Research design and the 2x2 table**

**Relative risk calculation**

Relative risk is used to establish treatment effects in

**and can generate a measure of**__prospective studies____, or__**incidence****the number of new cases in a given population**. Relative risk is a measure that from both a mathematical and practical standpoint makes more sense to investigators and clinicians. First of all, look at the underlying math associated with the calculation:**Relative risk is a direct comparison of risk ratios**

In comparison to the calculations for odds ratios, you can see here that the underlying mathematical reasoning of relative risk does not "cross-over" into other levels of exposure, but instead provides an actual comparison of risk ratios between independent groups.

Below, one can see the difference between the 95% confidence interval formulae for odds ratios and relative risk.

**Relative risk and 95% confidence intervals are more precise measures in comparison to odds ratios**

You can see that the underlying mathematics have yielded a different treatment effect from an odds ratio, RR = 3.57 (95% CI 2.38-5.36). This comparison of actual risk ratios yields a stronger measure of association than odds ratios and helps establish the incidence of disease in populations. The effects of the sample size from the earlier odds ratio calculations holds true here as well. Larger sample sizes will lead to more constricted and precise treatment effects, especially when using prospective designs and calculating relative risk.

Click on the

**Incid****ence**button to continue. Click on the**Download Database**button for a database structured for relative risk data. Click on the**Download Calculator**button to download a free epidemiological calculator.## Hire A Statistician - Statistical Consulting for Students

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