Filemaker version? OS (Win or Mac) version?
How are you making backups? Save as a Copy would be safe - Save onto another device - Flash Drive or computer or hard drive.
Save As MyFile01, MyFile02, etc
Duplicating the unopened file in Finder or Explorer would be safe also.
The medical information is imported PDFs or scans or manually entered?
Well, I use a usb hard drive and a sync app.
The info is manually entered, but images are in a separated folder (to avoid giga-size filemaker file)
And just as the images, separated data tables would be useful for backup (I guess).
There are advantages to using a Convert to Seperation Model, but I don't see much advantage when it comes to backing up your data. Either way, you have to make copies of your file. In addition to what DavidAnders has recommended, you can use FileMaker Server to make regular back up copies of your open files.
The key thing to avoid is to not use the OS or a backup utility to make back up copies of your files while they are open. Use FileMaker or Server to make a copy or close the files first. Then use the OS or utility to backup this closed copy of your file.
I will take a look into filemaker server.
Thanks a lot!