Hospitals, Police, Fire Rescue, and most Doctors only use Windows so if this is for emergency purposes, we recommend that you use the Windows format because those aboves cannot read the Mac format… but you may choose Mac if you prefer the software to work on Apple based computers only.
If your Mac is not able to read a Windows program, you would have had to go to a public library or use a friends PC to load your information on a PC only chip. If you only got the Mac version 99.5% of the first responders would not be able to read your important medical data.
IN NEWER MACS THEY HAVE A PROGRAM CALLED PARALLELS WHICH PERMITS YOU TO RUN WINDOWS PROGRAMS ON A MAC. IF YOU ARE NOT SURE IF YOU HAVE IT CALL 1-800-MY APPLE AND ASK THEM.