title: Performance of the Manchester Triage System in Adult Medical Emergency Patients: A Prospective Cohort Study.
abstract: BACKGROUND
  Accurate initial patient triage in the emergency department (ED) is pivotal in reducing time to effective treatment by the medical team and in expediting patient flow. The Manchester Triage System (MTS) is widely implemented for this purpose. Yet the overall effectiveness of its performance remains unclear.
  
  
  OBJECTIVE
  We investigated the ability of MTS to accurately assess high treatment priority and to predict adverse clinical outcomes in a large unselected population of medical ED patients.
  
  
  METHODS
  We prospectively followed consecutive medical patients seeking ED care for 30 days. Triage nurses implemented MTS upon arrival of patients admitted to the ED. The primary endpoint was high initial treatment priority adjudicated by two independent physicians. Secondary endpoints were 30-day all-cause mortality, admission to the intensive care unit (ICU), and length of stay. We used regression models with area under the receiver operating characteristic curve (AUC) as a measure of discrimination.
  
  
  RESULTS
  Of the 2407 patients, 524 (21.8%) included patients (60.5 years, 55.7% males) who were classified as high treatment priority; 3.9% (n = 93) were transferred to the ICU; and 5.7% (n = 136) died. The initial MTS showed fair prognostic accuracy in predicting treatment priority (AUC 0.71) and ICU admission (AUC 0.68), but not in predicting mortality (AUC 0.55). Results were robust across most predefined subgroups, including patients diagnosed with infections, or cardiovascular or gastrointestinal diseases. In the subgroup of neurological symptoms and disorders, the MTS showed the best performance.
  
  
  CONCLUSIONS
  The MTS showed fair performance in predicting high treatment priority and adverse clinical outcomes across different medical ED patient populations. Future research should focus on further refinement of the MTS so that its performance can be improved.
  
  
  BACKGROUND
  Clinicaltrials.gov: NCT01768494.
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Deborah
authors.initials: D
authors.lastname: Steiner
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Renetseder
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kutz
authors.affiliation: University Clinic of Infectious Diseases, University Hospital Bern, Bern, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Haubitz
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland; Department of Psychology, University of Bern, Bern, Switzerland.
authors.forename: Lukas
authors.initials: L
authors.lastname: Faessler
authors.affiliation: Medical Linguistics Consulting, North Olmsted, Ohio.
authors.forename: Janet Byron
authors.initials: JB
authors.lastname: Anderson
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Svenja
authors.initials: S
authors.lastname: Laukemann
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Anna Christina
authors.initials: AC
authors.lastname: Rast
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Susan
authors.initials: S
authors.lastname: Felder
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Antoinette
authors.initials: A
authors.lastname: Conca
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Reutlinger
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Marcus
authors.initials: M
authors.lastname: Batschwaroff
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Petra
authors.initials: P
authors.lastname: Tobias
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Buergi
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Beat
authors.initials: B
authors.lastname: Mueller
authors.affiliation: University Department of Internal Medicine, Medical Faculty of the University of Basel, Kantonsspital Aarau, Aarau, Switzerland.
authors.forename: Philipp
authors.initials: P
authors.lastname: Schuetz
mesh_terms: D004636:Emergency Service, Hospital / Q000458:organization & administration*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011446:Prospective Studies; D013557:Switzerland; D014218:Triage / Q000379:methods*; D014947:Wounds and Injuries / Q000401:mortality / Q000628:therapy*
keywords: Manchester triage system; emergency department; injury severity; mortality; triage