Inconsistent SpO2 Desat Event Counts OSCAR vs SpO2 Assistant

[SleepyTimeTime]

I just took delivery of my Contec CMS-50F pulse oximeter and used it for two nights. (figuring out how to get data into OSCAR was a chore).

I see that the number of SpO2 desaturation events reported in "SpO2 Assistant" and OSCAR are very different. I have both programs set up to count an event as 4% desat for >= 10 seconds.

Date         OSCAR    SpO2 Assistant  Manual Count*
2020-01-24    95      87              Not done yet
2020-01-25   197      46              43

Those are big discrepancies between OSCAR and SpO2 Assistant. I saw a thread on this titled "Oximeter software" by user "Asjb" on 12/12/15, but there were no answers.

Yes, I triple-confirmed that the parameters in both OSCAR and SpO2 Assistant are the same.

The manual count on Jan 25 using Excel is very close to what SpO2 reported.


Anybody have any ideas? Is this a bug in OSCAR? This can't be a hard calculation so I expected to see the same results.

*I used Excel to count the desats in the CSV file from the Contec unit. I set up columns with sliding windows of 1 to 10 seconds (using OFFSET) and used Conditional Formatting to highlight the desats >4%. 

[Jeff8356]

I noticed the same thing when I started importing data from my 50F.  Only difference I noticed was that OSCAR uses a higher baseline (usually between 95% and Max in the statistics panel).  Whereas SpO2 Assistant uses a lower baseline (more around your Med. in the statistics panel).
Not sure why there is a discrepancy, or which one is correct though.