title: Oxygen Desaturation Index Differs Significantly Between Types of Sleep Software.
abstract: OBJECTIVE
  The aim of this study was to compare the oxygen desaturation index (ODI) generated by two different sleep software systems.
  
  
  METHODS
  Participants undergoing diagnostic polysomnography for suspected obstructive sleep apnea underwent simultaneous oximetry recording using the ResMed ApneaLink Plus device (AL) and Compumedics Profusion PSG3 system (Comp). The ODI was calculated by the algorithms in the respective software of each system. To determine if differences were due to algorithm or recording devices, the Comp software was also used to generate ODI values using oximetry data from the AL.
  
  
  RESULTS
  In 106 participants, there was good correlation but poor agreement in the ODI generated by the two systems. AL ODI values tended to be higher than Comp ODI values, but with significant variability. For ODI4%, bias was 4.4 events/h (95% limits of agreement -5.8 to 14.6 events/h). There was excellent correlation and agreement when the same oximetry raw data was analyzed by both systems. For ODI4%, bias was 0.03 events/h (95% limits of agreement -2.7 to 2.8 events/h). Similar results were evident when the ODI3% was used.
  
  
  CONCLUSIONS
  There is a clinically significant difference in ODI values generated by the two systems, likely due to device signal processing, rather than difference in ODI calculation algorithms.
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Ng
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|School of Clinical Sciences, Monash University, Victoria, Australia.|Monash Partners, Epworth, Victoria, Australia.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Joosten
authors.affiliation: Sleep and Circadian Medicine Laboratory, Department of Physiology, Monash University, Victoria, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Edwards
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.
authors.forename: Anthony
authors.initials: A
authors.lastname: Turton
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.
authors.forename: Helen
authors.initials: H
authors.lastname: Romios
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|Hudson Institute of Medical Research, Victoria, Australia.
authors.forename: Thilini
authors.initials: T
authors.lastname: Samarasinghe
authors.affiliation: Sleep and Circadian Medicine Laboratory, Department of Physiology, Monash University, Victoria, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.
authors.forename: Shane
authors.initials: S
authors.lastname: Landry
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|Monash Partners, Epworth, Victoria, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.
authors.forename: Darren R
authors.initials: DR
authors.lastname: Mansfield
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|School of Clinical Sciences, Monash University, Victoria, Australia.|Monash Partners, Epworth, Victoria, Australia.
authors.forename: Garun S
authors.initials: GS
authors.lastname: Hamilton
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation* / Q000379:methods*; D010100:Oxygen / Q000032:analysis*; D012372:ROC Curve; D015203:Reproducibility of Results; D012984:Software
chemical_list: D010100:Oxygen
keywords: cardiovascular diseases; correlation; obstructive sleep apnea; oximetry; polysomnography