title: Validation of the San Francisco Syncope Rule in two hospital emergency departments in an Asian population.
abstract: OBJECTIVE
  The objective was to externally validate the ability of the San Francisco Syncope Rule (SFSR) to accurately identify patients who will experience a 7-day serious clinical event in an Asian population.
  
  
  METHODS
  This was a prospective cohort study, with a sample of adult patients with syncope and near-syncope enrolled. Patients 12 years old and below and patients with loss of consciousness after head trauma, a witnessed seizure, with known alcohol or illicit drug ingestion, and altered level of consciousness or persistent new neurologic deficits were excluded. The patients were evaluated for the presence of one or more of the five SFSR variables: shortness of breath, history of heart failure, hematocrit <30%, systolic blood pressure <90 mm Hg, and abnormal electrocardiogram (ECG). The patients were followed up by medical record review or telephone interview. Seven-day outcomes were death, arrhythmia, myocardial infarction, acute pulmonary edema, significant structural heart disease, pulmonary embolism, major cardiac procedure, stroke, subarachnoid hemorrhage, major bleeding, and anemia.
  
  
  RESULTS
  A total of 1,250 patients from two centers were recruited. Fifty-six patients were excluded from primary analysis because of incomplete data (n = 55) and/or they were noncontactable for follow-up (n = 32). Of the 1,194 patients analyzed, 138 patients (11.6%) experienced adverse outcomes at 7 days. The rule performed with a sensitivity of 94.2% (95% confidence interval [CI] = 89.0% to 97.0%) and a specificity of 50.8% (95% CI = 47.7% to 53.8%).
  
  
  CONCLUSIONS
  In this study, SFSR rule had a sensitivity of 94.2%. This suggests caution on the strict application of the rule to all patients presenting with syncope. It should only be used as an aide in clinical decision-making in this population.
authors.affiliation: Emergency Medicine Department, Changi General Hospital, 2 Simei Street 3, Singapore 529889. camlyn_tan@cgh.com.sg
authors.forename: Camlyn
authors.initials: C
authors.lastname: Tan
authors.forename: Tiong Beng
authors.initials: TB
authors.lastname: Sim
authors.forename: Shin Ying
authors.initials: SY
authors.lastname: Thng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000175:diagnosis / Q000453:epidemiology; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000453:epidemiology; D044466:Asian People; D015331:Cohort Studies; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis / Q000453:epidemiology; D006333:Heart Failure / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000453:epidemiology; D018570:Risk Assessment / Q000379:methods; D012720:Severity of Illness Index; D012846:Singapore / Q000453:epidemiology; D013575:Syncope / Q000150:complications* / Q000175:diagnosis* / Q000208:ethnology; D055815:Young Adult