The Variable IsActive flag allows for a soft delete of a variable.  To deactivate a variable, go to Edit/View Variables and uncheck the IsActive flag:

When a variable's IsActive flag is not checked it has the affects.

1. The column will not appear in Monthly Data Entry Forms.

2. Cells in Custom Data Entry that are linked to the variable, will say "Deleted" and not allow any data entry.

3. The variable will not show in the Variable Browser.  To see inactive variables in the browser, check the Show Inactive and Inactive variables will be displayed (the row will be struck thru indicating the variable is inactive):

4. Future Due Lab Cal Samples will not show the Test/Variable. Does not affect any samples that are in progress or in history. 

5. Reports/Graphs etc... are not affected.