title: Medical emergency team activation: performance of conventional dichotomised criteria versus national early warning score.
abstract: BACKGROUND
  To activate the hospital's medical emergency team (MET), either conventional dichotomised activation criteria or an early warning scoring system may be used. The relative performance of these different activation patterns to discriminate high risk patients in a heterogenic general ward population after adjustment for multiple confounding factors has not been evaluated. We aimed to evaluate the dichotomised activation criteria used at our institution and the recently published national early warning score (NEWS, United Kingdom).
  
  
  METHODS
  Prospective point prevalence study at a university hospital in Finland. On two separate days, the vital signs of all adult patients without treatment limitations were measured. Data on cumulative comorbidity (Charlson comorbidity index), age, gender, admission characteristics and subsequent mortality were collected. Univariate and multivariate logistic regression models were used for unadjusted and adjusted performance testing.
  
  
  RESULTS
  The cohort consisted of 615 patients. The dichotomised activation criteria were not associated with in-hospital serious adverse events (odds ratio 1.87, 95% confidence interval 0.55-6.30) or 30-day mortality (2.13, 0.79-5.72) after adjustments. For a NEWS of seven or more (the suggested trigger level for immediate MET activation), the adjusted odds ratios for the above mentioned outcomes were 7.45 (2.39-23.3) and 11.4 (4.40-29.6), respectively. Unlike the dichotomised activation criteria, NEWS was also independently associated with a higher 60- and 180-day mortality after adjustments.
  
  
  CONCLUSIONS
  NEWS discriminates high risk patients in a heterogenic general ward population independently of multiple confounding factors. The conventional dichotomised activation criteria were not able to detect high risk patients.
authors.affiliation: Department of Intensive Care Medicine and Critical Care Medicine Research Group, Tampere University Hospital, Tampere, Finland; Medical School, University of Tampere, Tampere, Finland.
authors.forename: Joonas
authors.initials: J
authors.lastname: Tirkkonen
authors.forename: Klaus T
authors.initials: KT
authors.lastname: Olkkola
authors.forename: Heini
authors.initials: H
authors.lastname: Huhtala
authors.forename: Jyrki
authors.initials: J
authors.lastname: Tenhunen
authors.forename: Sanna
authors.initials: S
authors.lastname: Hoppu
mesh_terms: D017677:Age Distribution; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D001831:Body Temperature / Q000502:physiology; D015331:Cohort Studies; D015897:Comorbidity; D004632:Emergency Medical Services / Q000458:organization & administration* / Q000706:statistics & numerical data; D005260:Female; D005387:Finland / Q000453:epidemiology; D006339:Heart Rate / Q000502:physiology; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010348:Patient Care Team / Q000458:organization & administration* / Q000706:statistics & numerical data; D015995:Prevalence; D011446:Prospective Studies; D015203:Reproducibility of Results; D056152:Respiratory Rate; D012306:Risk; D017678:Sex Distribution; D016896:Treatment Outcome; D055986:Vital Signs