If you use the “Universal” version of Google Analytics, the method used to track data has changed. Data from your A/B tests is now sent to Google Analytics in the form of dimensions, rather than in custom variables.
You must therefore declare these dimensions beforehand, so that the data can be sent to Universal Analytics. To do this, select “Admin” at the top of the page:
Select the property in which you would like to view the data and click “Custom Definitions”:
Select “Custom Dimensions”:
Click “New Custom Dimension”:
Add the name of your dimension, choose “User” as the scope, and create your dimension:
Note that if you would like to integrate data with dimension 4, you will need to declare four dimensions in Universal Analytics. The first dimension you create will have the number 1, and the numbers will increase as you add new dimensions.
To access your data, you must then create a custom report containing the indicators that you want to follow as metrics, and the dimension that you have just created. To find out more, visit the following page: https://support.google.com/analytics/answer/1151300?hl=en&ref_topic=1012046 )