title: The Performance of a Mobile Phone Respiratory Rate Counter Compared to the WHO ARI Timer.
abstract: OBJECTIVE
  To compare the accuracy and efficiency of the respiratory rate (RR) RRate mobile application to the WHO ARI Timer.
  
  
  METHODS
  Volunteers used both devices to measure RR from reference videos of infants and children. Measurements were compared using correlation, Bland-Altman analysis, error metrics and time taken.
  
  
  RESULTS
  Measurements with either device were highly correlated to the reference (r = 0.991 and r = 0.982), and to each other (r = 0.973). RRate had a larger bias than the ARI Timer (0.6 vs. 0.04 br/min), but tighter limits of agreement (-4.5 to 3.3 br/min vs. -5.5 to 5.5 br/min). RRate was more accurate than the ARI Timer (percentage error 10.6% vs. 14.8%, root mean square error 2.1 vs. 2.8 br/min and normalized root mean square error 5.6% vs. 7.5%). RRate measurements were 52.7 seconds (95% CI 50.4 s to 54.9 s) faster.
  
  
  CONCLUSIONS
  During video observations, RRate measured RR quicker with a similar accuracy compared to the ARI Timer.
authors.affiliation: Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver BC, Canada.|Department of Anaesthesia, Guy's & St Thomas' NHS Foundation Trust, London, UK.
authors.forename: Heng
authors.initials: H
authors.lastname: Gan
authors.affiliation: Department of Health Sciences and Technology, ETH Zurich, Switzerland.
authors.forename: Walter
authors.initials: W
authors.lastname: Karlen
authors.affiliation: Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver BC, Canada.
authors.forename: Dustin
authors.initials: D
authors.lastname: Dunsmuir
authors.affiliation: Department of Statistics, University of British Columbia, Vancouver BC, Canada.
authors.forename: Guohai
authors.initials: G
authors.lastname: Zhou
authors.affiliation: Faculty of Medicine, University of British Columbia, Vancouver BC, Canada.
authors.forename: Michelle
authors.initials: M
authors.lastname: Chiu
authors.affiliation: Department of Electrical & Computer Engineering, University of British Columbia, Vancouver BC, Canada.
authors.forename: Guy A
authors.initials: GA
authors.lastname: Dumont
authors.affiliation: Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver BC, Canada.
authors.forename: J Mark
authors.initials: JM
authors.lastname: Ansermino
mesh_terms: D000328:Adult; D040421:Cell Phone; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D063731:Mobile Applications; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods*; D056152:Respiratory Rate