title: Apples to apples or apples to oranges? International variation in reporting of process and outcome of care for out-of-hospital cardiac arrest.
abstract: OBJECTIVE
  Survival after out-of-hospital cardiac arrest (OHCA) varies between communities, due in part to variation in the methods of measurement. The Utstein template was disseminated to standardize comparisons of risk factors, quality of care, and outcomes in patients with OHCA. We sought to assess whether OHCA registries are able to collate common data using the Utstein template. A subsequent study will assess whether the Utstein factors explain differences in survival between emergency medical services (EMS) systems.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  This retrospective analysis of prospective cohorts included adults treated for OHCA, regardless of the etiology of arrest. Data describing the baseline characteristics of patients, and the process and outcome of their care were grouped by EMS system, de-identified, and then collated. Included were core Utstein variables and timed event data from each participating registry. This study was classified as exempt from human subjects' research by a research ethics committee.
  
  
  RESULTS
  Thirteen registries with 265 first-responding EMS agencies in 13 countries contributed data describing 125,840 cases of OHCA. Variation in inclusion criteria, definition, coding, and process of care variables were observed. Contributing registries collected 61.9% of recommended core variables and 42.9% of timed event variables. Among core variables, the proportion of missingness was mean 1.9±2.2%. The proportion of unknown was mean 4.8±6.4%. Among time variables, missingness was mean 9.0±6.3%.
  
  
  CONCLUSIONS
  International differences in measurement of care after OHCA persist. Greater consistency would facilitate improved resuscitation care and comparison within and between communities.
authors.affiliation: University of Washington, Harborview Center for Prehospital Emergency Care, Department of Medicine, University of Washington, Seattle, WA, United States.
authors.forename: Chika
authors.initials: C
authors.lastname: Nishiyama
authors.affiliation: University of Washington Clinical Trial Center, Department of Biostatistics, University of Washington, Seattle, WA, United States.
authors.forename: Siobhan P
authors.initials: SP
authors.lastname: Brown
authors.affiliation: University of Washington Clinical Trial Center, Department of Biostatistics, University of Washington, Seattle, WA, United States.
authors.forename: Susanne
authors.initials: S
authors.lastname: May
authors.affiliation: Kyoto University Health Service, Kyoto, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Iwami
authors.affiliation: Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Rudolph W
authors.initials: RW
authors.lastname: Koster
authors.affiliation: Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Stefanie G
authors.initials: SG
authors.lastname: Beesems
authors.affiliation: Helsinki Emergency Medical Service, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Markku
authors.initials: M
authors.lastname: Kuisma
authors.affiliation: Helsinki Emergency Medical Service, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Ari
authors.initials: A
authors.lastname: Salo
authors.affiliation: St John Ambulance, Perth, WA, Australia; University of Western Australia, Perth, WA, Australia.
authors.forename: Ian
authors.initials: I
authors.lastname: Jacobs
authors.affiliation: University of Western Australia, Perth, WA, Australia; Monash University, Melbourne, Vic., Australia.
authors.forename: Judith
authors.initials: J
authors.lastname: Finn
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, and Municipal Ambulance Service, Vienna, Austria.
authors.forename: Fritz
authors.initials: F
authors.lastname: Sterz
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, and Municipal Ambulance Service, Vienna, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Nürnberger
authors.affiliation: University of Western Australia, Perth, WA, Australia; Monash University, Melbourne, Vic., Australia; Ambulance Victoria, Vic., Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Smith
authors.affiliation: Rescu, Li Ka Shing Knowledge Institute, St. Michael's Hospital and Division of Emergency Medicine, Department of Medicine, University of Toronto, Toronto, Ont., Canada.
authors.forename: Laurie
authors.initials: L
authors.lastname: Morrison
authors.affiliation: Oslo University Hospital, Oslo, Norway.
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Olasveengen
authors.affiliation: Department of Emergency Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States.
authors.forename: Clifton W
authors.initials: CW
authors.lastname: Callaway
authors.affiliation: Seoul National University, College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang Do
authors.initials: SD
authors.lastname: Shin
authors.affiliation: Department of Anesthesiology and Intensive Medicine, University-Medical Center Hospital, Schleswig-Campus Kiel, Kiel, Germany.
authors.forename: Jan-Thorsten
authors.initials: JT
authors.lastname: Gräsner
authors.affiliation: Department of Emergency Medicine, Oregon Health and Science University, Portland, OR, United States.
authors.forename: Mohamud
authors.initials: M
authors.lastname: Daya
authors.affiliation: Department of Emergency Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Matthew Huei-Ming
authors.initials: MH
authors.lastname: Ma
authors.affiliation: University of Borås, Sahlgrenska University Hospital, Göteborg, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Herlitz
authors.affiliation: School of Health and Social Sciences, University of Dalarna, Falun, Sweden.
authors.forename: Anneli
authors.initials: A
authors.lastname: Strömsöe
authors.affiliation: Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee, WI, United States.
authors.forename: Tom P
authors.initials: TP
authors.lastname: Aufderheide
authors.affiliation: Discipline of General Practice, National University of Ireland, Galway, Ireland and Department of Public Health Medicine, Health Service Executive, Donegal, Ireland.
authors.forename: Siobhán
authors.initials: S
authors.lastname: Masterson
authors.affiliation: Department of Emergency Medicine, University of Alabama School of Medicine, Birmingham, AL, United States.
authors.forename: Henry
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Emergency Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Jim
authors.initials: J
authors.lastname: Christenson
authors.affiliation: Department of Emergency Medicine, University of Ottawa, Ottawa, Ont., Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Stiell
authors.affiliation: Department of Emergency Medicine, University of California San Diego, San Diego, CA, United States.
authors.forename: Dan
authors.initials: D
authors.lastname: Davis
authors.affiliation: University of Washington, Harborview Center for Prehospital Emergency Care, Department of Medicine, University of Washington, Seattle, WA, United States.
authors.forename: Ella
authors.initials: E
authors.lastname: Huszti
authors.affiliation: University of Washington, Harborview Center for Prehospital Emergency Care, Department of Medicine, University of Washington, Seattle, WA, United States; University of Washington Clinical Trial Center, Department of Biostatistics, University of Washington, Seattle, WA, United States. Electronic address: nichol@uw.edu.
authors.forename: Graham
authors.initials: G
authors.lastname: Nichol
mesh_terms: D000328:Adult; D016887:Cardiopulmonary Resuscitation / Q000379:methods / Q000401:mortality*; D015331:Cohort Studies; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D006801:Humans; D038622:Internationality; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Cardiac arrest; Cardiopulmonary resuscitation; Epidemiology; Resuscitation; Utstein template