There is no method that does not involve macros.

If you are sharing these and the macros are not implemented system-wide it is likely to be problematic. See Add Interactive Toogle or Sequenced Object to Document and my own Check-Box Add-In for ideas. Mine is based on the methods used in the FAX template distributed with Word 97. Those work in any later version of Word. More on these can be found in Single-Click Checkboxes in Word.

With a formfield checkbox, you can right-click on it and change it to "checked" or "unchecked."