--- title: Paired data description: "\"Data are called paired when you choose to compare the subjects of your study two by two instead of comparing one whole group to another whole group. The…" --- [Skip to content](https://help.easymedstat.com/support/solutions/articles/77000401292-paired-data#main-content) English Show submenu for translations ![](https://help.easymedstat.com/hs-fs/hubfs/Logo%20EMS%20HQ%20Noir-1.png?width=366&height=70&name=Logo%20EMS%20HQ%20Noir-1.png) Open main navigation Close main navigation - English Show submenu for translations - [Open a ticket](https://t3jiy.share-eu1.hsforms.com/2pRawwxfuSS6Scx4Qn4KSPA) [Open a ticket](https://t3jiy.share-eu1.hsforms.com/2pRawwxfuSS6Scx4Qn4KSPA) How can we help you? - There are no suggestions because the search field is empty. 1. [EasyMedStat Knowledge Base](https://help.easymedstat.com/?hsLang=en) 2. [Statistical analyses](https://help.easymedstat.com/statistical-analyses?hsLang=en) 3. [Statistical tests](https://help.easymedstat.com/statistical-analyses?hsLang=en#statistical-tests) # Paired data # Definition Data are called paired when you choose to **compare the subjects** of your study **two by two** instead of comparing one whole group to another whole group. The data from the two groups will be compared with a paired test. # In practice Paired data are usually used in **case-control** studies but also in other study types as **before-after** studies or **[correlation analyses](https://help.easymedstat.com/support/solutions/articles/77000356204-the-pearson-s-correlation?hsLang=en)**. In the case of case-control studies, the main advantages of this type of design are to control chosen confusion biases and to reduce the within-subject variability. It may also need a smaller sample size than others study types. The inconveniences of this design are a) that the data used for matching cannot be studied if the matching were performed at the participant selection, b) a bad matching will lead to biased conclusions and c) the cutoff of numeric data to paired people could be difficult to find. In the case of before-after studies and correlation analyses, the data are analyzed from the same patients. For example, you could look for a correlation between the age of patients and their systolic blood pressure. In this case, each age is matched with the same patient's systolic blood pressure. # How to use it on EasyMedStat? To do a Student's paired test or a Wilcoxon's Rank Signed test 1. Select two Numeric variables you would like to compare 2. Click on "Which tests can I do ?" 3. Click on "Compare values of ... between groups of patients" To do a McNemar's test 1. Select two Yes-No variables you would like to compare 2. Click on "Which tests can I do ?" 3. Click on "Compare pre-post treatment proportions" # See also - [The Student's paired test](https://help.easymedstat.com/support/solutions/articles/77000401223-the-student-s-paired-test?hsLang=en) - [The McNemar's test](https://help.easymedstat.com/support/solutions/articles/77000401688-the-mcnemar-s-test?hsLang=en) - [The Wilcoxon's Ranked Signed test](https://help.easymedstat.com/support/solutions/articles/77000401288-the-wilcoxon-s-signed-rank-test?hsLang=en) - [Account](https://help.easymedstat.com/account?hsLang=en#main-content) - [Account](https://help.easymedstat.com/account?hsLang=en#account) - [Collect data](https://help.easymedstat.com/collect-data?hsLang=en#main-content) - [Questionnaires (ePRO)](https://help.easymedstat.com/collect-data?hsLang=en#questionnaires-epro) - [Add and edit patients](https://help.easymedstat.com/collect-data?hsLang=en#add-and-edit-patients) - [Randomization](https://help.easymedstat.com/collect-data?hsLang=en#randomization) - [Export](https://help.easymedstat.com/collect-data?hsLang=en#export) - [Create a series / eCRF](https://help.easymedstat.com/collect-data?hsLang=en#create-a-series-ecrf) - [Multilingual studies](https://help.easymedstat.com/collect-data?hsLang=en#multilingual-studies) - [Variables](https://help.easymedstat.com/variables?hsLang=en#main-content) - [Organize in categories](https://help.easymedstat.com/variables?hsLang=en#organize-in-categories) - [Dynamic Variables](https://help.easymedstat.com/variables?hsLang=en#dynamic-variables) - [Manage variables](https://help.easymedstat.com/variables?hsLang=en#manage-variables) - [Statistical analyses](https://help.easymedstat.com/statistical-analyses?hsLang=en#main-content) - [Statistical tests](https://help.easymedstat.com/statistical-analyses?hsLang=en#statistical-tests) - [Compare groups](https://help.easymedstat.com/statistical-analyses?hsLang=en#compare-groups) - [Multivariate analysis](https://help.easymedstat.com/statistical-analyses?hsLang=en#multivariate-analysis) - [Filter patients](https://help.easymedstat.com/statistical-analyses?hsLang=en#filter-patients) - [Descriptive Statistics](https://help.easymedstat.com/statistical-analyses?hsLang=en#descriptive-statistics) - [Collaborate](https://help.easymedstat.com/collaborate?hsLang=en#main-content) - [Share your series](https://help.easymedstat.com/collaborate?hsLang=en#share-your-series) - [Manage your organization](https://help.easymedstat.com/collaborate?hsLang=en#manage-your-organization) - [Monitoring](https://help.easymedstat.com/monitoring?hsLang=en#main-content) - [Automations](https://help.easymedstat.com/monitoring?hsLang=en#automations) - [Electronic Signatures](https://help.easymedstat.com/monitoring?hsLang=en#electronic-signatures) - [Queries](https://help.easymedstat.com/monitoring?hsLang=en#queries) - [Clean data](https://help.easymedstat.com/monitoring?hsLang=en#clean-data) [![](https://help.easymedstat.com/hs-fs/hubfs/Logo%20EMS%20HQ%20Noir-1.png?width=366&height=70&name=Logo%20EMS%20HQ%20Noir-1.png)](http://www.easymedstat.com) [mailto:support@easymedstat.com](mailto:support@easymedstat.com) Copyright © 2026, EasyMedStat