Does anyone know how to convert from mV/cm to % O2 in an EDF file?

[erouting]

Following a HIPAA complaint I finally got my raw sleep study data. In order to make sure it's actually my data and not some random file they sent me I need to look through it and make sure their claimed report is a reasonable interpretation of this file. To do that I need the units to match. My EDF viewer (using EDFBrowser at the moment) seems to displays the oxygen level (pleth) in mV/cm. I need to convert that to %O2 so that it matches the report. Does anyone know what the formula for that is or does it vary by device?

Thanks

[erouting]

I figured it out, the O2 data was there in a different channes but they looked flat because the scale was incorrect, system expected percent in hundreds, but was being given as a decimal, which caused it to appear not to change at all.