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XML has less events comparing to AHI

Hi,

This is somewhat related to this post.

I am checking the MrOS dataset and feel XML annotations might missing significant amout of apnea/hypopnea events.

Here is an example in visit2, in the file "mros-visit2-aa0181-nsrr.xml", there is, in total, 104 events,

{'Obstructive apnea|Obstructive Apnea': 86, 'Hypopnea|Hypopnea': 17, 'Central apnea|Central Apnea': 1}

while the CSV "mros-visit2-dataset-0.6.0.csv", says AHI is 71 (from "poahi3"). The total sleep time is 6 hours as potmrem = '75', potmst1 ='21', potmst2 = '264', potmst34 = '0'.

Thus there should be 71 * 6 = 426 events.

Am I missing something? I can understand XML might have more events than the CSV varialbe as it may need to be filtered. But I cannot figure it out why sometimes the XML file have less events.

Thanks for your help, Hao.

Thanks for raising this issue. Please check out the Hypopnea event tags section on this page: https://sleepdata.org/datasets/mros/pages/polysomnography-introduction.md

In short, look for events tagged as "Unsure" in the XML files. These are also hypopneas that can be included in the numerator for AHI metrics. There appear to be 353 Unsure events for aa0181 at Visit 2.

Thanks a lot for the quick reply. It is super helpful!