This capability is restricted to users with Project Owner permissions on a given project.
XNAT's core data types are built to be extensible to reflect the shape and organization of your study data. There are two ways to reflect a data type in XNAT – install a data type plugin, or extend an existing data type through a custom variable. If you want your changes to take effect site-wide, you should install a new data type. But if your changes are meant to be project-specific, it will be most expedient to follow this documentation to add a custom variable within your project.
To create custom variables, click on Manage Custom Variables in the Details tab at the top of your Project report page. This will bring up the Custom Variable management interface.
You have the ability to add variables to the subject, or any experiment data type that is available to your project. Select the appropriate data type from the drop down list. This will display the predefined variable sets. Some of these sets were created by XNAT at installation, others may have been added by other users.
First, review these predefined variable sets to see if your variables have already been created. If not, click Add a Custom Variable Set. This will bring up the form for adding your custom variables. Each variable must be contained within a variable set.
Next, define a name for your set (used in the forms and report to group your variables) and a description.
Then add one or more variables.
When you have finished making your desired changes, click the Save button at the bottom of the screen.
Your customizations will be lost if you don’t save them.