Track Changes Of Raw Table Data Information?

Im working in MS Access 2003.Im creating an audit trail for users actions in a form, to monitor and keep track of what fields were updated/entered/removed from the database, these actions are essentially done from command buttons (and the audit trail, is coded on the button click)

However, I have a few search screens, that return a subform listing results. These datasheets returned are effectivly like opening the raw table and hence are editable, (permission to change is granted as they are admin only searches, yes, they can change the raw table)

How can I track the change to a raw table field, ie, if someone updates the field SURNAME from 'Smth' to 'Smith', is there something that triggers this (obviously if it was in an interface textbox, you could audit this) is their a field change. The only way i can suggest it make a recordset of the intial results, then compare that to the results in the table as they leve and compare the two.