rdi - Search - Sleep Data - National Sleep Research Resource

Apnea-Hypopnea Index (AHI): (All apneas with no oxygen desaturation threshold used + hypopneas with > 30% flow reduction and with >= 4% oxygen desaturation ) / hour of estimated sleep from type III home sleep test

aphypi under Sleep Monitoring/Home Sleep Test in HOMEPAP variables

Calculated - Summary metric of sleep disordered breathing events. Estimated sleep duration, providing an approximation of total sleep duration (i.e. total sleep time) inferred from analysis of non-EEG channels Zhao et al., 2017 (PMID:27707441)The definition of hypopnea events is consistent with the following clinical guidelines: (1) AASM 2012 update (alternative) Berry RB et al. 2012 (PubMed ID:23066376), and (2) AASM 2015 (acceptable) [Berry RB et al. The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications, Version 2.2. American Academy of Sleep Medicine, Darien, IL, 2015.]. Search for all AHI variables consistent with the same clinical guidelines within this dataset

Polysomnography (PSG) Quality Assessment: Medical Alert - Apnea-Hypopnea Index (AHI) > 50

ahiov50 under Sleep Monitoring/Polysomnography/Signal Quality in SOF variables

Total Sleep Duration: the interval between sleep onset and sleep offset while the participant is asleep from type II polysomnography

slpprdp under Sleep Monitoring/Polysomnography/Sleep Architecture in SHHS variables

Conventionally this variable would be called total sleep time (TST)(i.e. total time spent in stage 1 or greater).