Umm, maybe not.
OnDirty is a property https://support.office.com/en-us/art...3-dd01d0d14154
.Dirty is an event https://msdn.microsoft.com/en-us/lib.../ff835655.aspx
If you want an audit trail, yes you'd repeat some records, but not necessarily all fields. Patient info should be in one table, visit info in another. Each visit would be a record that you'd relate to the patient via a form bound to a query on those two (or more) tables. However, you would not repeat the patient info. Sounds like you might want to check out database normalization also.
BTW, most likely your message box didn't work because you're trying to pass a property to it. Message boxes are for text only (or anything that can be represented as text).
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.