Open AccessStaTips Part VIII: Confidence interval for the sample mean
Author(s) -
Giuseppe Perinetti
Publication year - 2020
Publication title -
south european journal of orthodontics and dentofacial research
Language(s) - English
Resource type - Journals
eISSN - 1849-5249
pISSN - 1849-3858
DOI - 10.5937/sejodr7-27200
Subject(s) - confidence interval , statistics , population mean , sample (material) , sample size determination , population , mean value , interval (graph theory) , mathematics , tolerance interval , interval estimation , mean difference , demography , combinatorics , physics , estimator , sociology , thermodynamics
When conducting research on a given type of patients, it is impossible to examine all the existing subjects of that type (population)to derive the true mean of the parameter of interest. More realistically, by the investigation of a small group of subjects (sample) fromthe whole population, researchers can estimate an interval into which the true mean of the population lies. In statistics, such interval isreferred to as confidence interval (CI). The calculation of the CI from a sample mean is simple and gives important information, not onlyregarding the true mean of the population, but also on the statistical significance of the difference between groups being compared. Forthese reasons, the reporting of the CIs is preferred over the p value alone.