title: The relationship between survival after out-of-hospital cardiac arrest and process measures for emergency medical service ambulance team performance.
abstract: OBJECTIVE
  International institutes have developed their own clinical performance indicators for ambulance services. It is unknown whether these process measures are related to survival of patients after out-of-hospital cardiac arrest (OHCA). We aimed to determine whether Emergency Medical Service (EMS)-related ambulance team process measures correlate with patient survival.
  
  
  METHODS
  Four years of observational data were collected from an urban EMS OHCA registry. The two process measures were achieving an EMS response time ≤4 min and prehospital ROSC (return of spontaneous circulation). The outcome measure was survival to discharge. We used the GLMM (generalised linear mixed model) with stepwise selection to examine this process-outcome link at the patient and EMS team levels, respectively.
  
  
  RESULTS
  We analyzed 3856 OHCA patients distributed across forty-three EMS ambulance teams. Survival to discharge was observed in 193 (5%) patients. The two EMS team process measures were positively associated with an improvement in survival at the patient level after case-mix adjustment. However, they were not associated with improvement in the risk-adjusted survival rate.
  
  
  CONCLUSIONS
  The EMS team-level process measures proposed by international institutes may not predict the risk-adjusted survival rate. Using these measures to motivate EMS teams to improve their quality performance would be questionable. Increased efforts should be devoted to constructing more pivotal EMS team-level process measures that are tightly linked to survival.
authors.affiliation: Department of Public Health, Fu Jen Catholic University, New Taipei, Taiwan.
authors.forename: Tsung-Tai
authors.initials: TT
authors.lastname: Chen
authors.affiliation: Department of Emergency Medicine, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan.
authors.forename: Matthew Huei-Ming
authors.initials: MH
authors.lastname: Ma
authors.affiliation: Department of Healthcare Administration, I-Shou University, Kaohsiung, Taiwan.
authors.forename: Fen-Ju
authors.initials: FJ
authors.lastname: Chen
authors.affiliation: Graduate Institute of Clinical Medicine and School of Nursing, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Fu-Chang
authors.initials: FC
authors.lastname: Hu
authors.affiliation: Department of Healthcare Administration, I-Shou University, Kaohsiung, Taiwan.
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Lu
authors.affiliation: Department of Emergency Medicine, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan.
authors.forename: Wen-Chu
authors.initials: WC
authors.lastname: Chiang
authors.affiliation: Department of Emergency Medicine, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan; Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan. Electronic address: patrick.patko@gmail.com.
authors.forename: Patrick Chow-In
authors.initials: PC
authors.lastname: Ko
mesh_terms: D000368:Aged; D000552:Ambulances; D005260:Female; D057209:Hospital Rapid Response Team; D006801:Humans; D008297:Male; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality* / Q000628:therapy*; D017064:Process Assessment, Health Care; D015996:Survival Rate
keywords: Cardiac arrest; Emergency medical services; Performance measurement; Process measures; Profiling