In Manage | database | Fields, you can click a field and click "delete".
I think thought that you have more issues than that. How do you currently handle situations where two patients have the same exact name? This is a far from uncommon situation and an issue that is especially critical for medical records like these.
I suggest you work towards adding a serial number field to your members table and using it to link to related records in contacts and Results.
You'll also need to remove duplicate records from your members table and this will be a problem if you have more than one member with the same name.
You may find it useful to read this White Paper for FMP Novices
A Google for "filemaker normalization" has a top link about your process
Normalizing Data on Import?
I am creating my first FileMaker 10 solution. My source data is a single Excel worksheet. My target FM schema is normalized into several tables.
The MRN is the medical record number and is unique to each patient. I am using it as my KEY Thanks
Sorry, missed that field in your original post.
Set up that field with a unique values, validate always validation rule and then when you import in the the members table, the duplicate entries will be automatically be filtered out.