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Confidence interval for a rate
A rate is a ratio between a count and another measurement, for example the ratio of a number of events observed and the total number of person-years of observation.
- Numerator: the observed number of events.
- Denominator: for example the total person-years.
- Option Express result as 1:X: when this option is selected the rate R will be displayed as 1:(1/R), e.g. the rate 10/200 equals 0.05 and can be represented as 1:20.
- The Poisson 95% Confidence Interval for the number counted (the Numerator).
- The incidence rate.
- The 95% Confidence Interval for the incidence rate.
- Daly LE (1998) Confidence limits made easy: interval estimation using a substitution method. American Journal of Epidemiology 147:783-790.
How to cite this page
- MedCalc Software Ltd. Confidence interval for a rate. https://www.medcalc.org/calc/rate_ci.php (Version 20.013; accessed September 25, 2021)