With the group test utility you are able to verify the Node Groups created.
The two functions of the group test are:
The following dropdown menus can be used to filter your options.
Using the filters the amount of options can be reduced, after which you may select a group to verify its contents.
The amount of nodes for the group are shown, as well as the logs. The logs explain how this conclusion came to be. Depending on the debug level chosen, it is more verbose.