Prior to Origin 2018, there is only global control of display digits via Digits in Report in the Numeric Format tab of Tools: Options.

In 2018, users can specify default Default Digits to apply for different types of analyses. For example:

After an analysis is done, right click in the table in the result sheet and choose Digits...  Set the Digits values and check Save as Default.

The default will apply to other instances of that particular analysis operation in the future.

To reset back to system default: Close Origin. Go to User Files folder and delete Defaults.XML.