Design Guidelines: Basic Rules
Larger groups of information units which are to be separated from one another are placed in a group box.
Group boxes only contain particular groups, not the entire screen.
Exceptions
Some information blocks do not require a group box.
Small information blocks which do not necessarily require separation from other information on the screen can be separated with a blank line.
Do not use group boxes for header data. Use a blank line to separate header data from other information on the screen.
Dialog boxes with only one information group do not contain a group box.
Subscreens
When using subscreens, the group box should be defined in the calling screen because two extra lines are to be specified for the box in the subscreen definition and the size of the area in the calling screen would have to be increased correspondingly.
Hiding
Group boxes can be hidden at runtime if all fields contained are also hidden.