How to create a new attribute, create new tables for attributes, and add an attribute to a record in The Raiser's Edge (includes video demo)
  • Note: on Step 5 in the article above, Choose Date Type of Table
    • For a Checkbox Attribute - Ensure "Allow Only 1 per Record" is not marked
    • For a Dropdown attribute - Ensure "Allow Only 1 per Record" is marked
Note: After creating table in Attributes, You must go to Config > tables and add an entry to the table. This entry will be the caption to the right of the checkbox.

For form specific documentation on how to add attributes, see the below article:
How to add custom fields to a Donation form
How do I add an additional field to an event form? (includes video demo)
How to add attributes to user email preferences part