title: The mortality benefit threshold for patients with suspected pulmonary embolism.
abstract: OBJECTIVE
  The mortality benefit for pulmonary embolism (PE) is the difference in mortality between treated and untreated patients. The mortality benefit threshold is the mortality benefit above which testing for a condition should be initiated and below which it should not. To illustrate this concept, the authors developed a decision model to estimate the mortality benefit threshold at several pretest probabilities for low-risk emergency department (ED) patients with possible PE and compare those thresholds with contemporary management of PE in the United States and what is known and not known about treatment benefits with anticoagulation.
  
  
  METHODS
  The authors built a decision model of a 25-year-old female with suspected PE. Model inputs were obtained from the literature or clinical judgment when data were unavailable. One-way sensitivity analysis was used to derive the mortality benefit threshold at several fixed pretest probabilities, and two-way sensitivity analysis was used to determine drivers of the mortality benefit threshold.
  
  
  RESULTS
  At a 15% pretest probability, the mortality benefit threshold was 3.7%; at 10% it was 5.2%; at 5% it was 9.8%; at 2% it was 23.5%; at 1% it was 46.3%; and at 0.5% it was 92.1%. In two-way sensitivity analyses, D-dimer specificity, CT angiography (CTA)/CT venography (CTV) sensitivity, annual cancer risk, probability of death from renal failure, and probability of major bleeding were major model drivers.
  
  
  CONCLUSIONS
  The mortality benefit threshold for initiating PE testing is very high at low pretest probabilities of PE, which should be considered by clinicians in their diagnostic approach to PE in the ED. The mortality benefit threshold is a novel way of exploring the benefits and risks of ED-based testing, particularly in situations like PE where testing (i.e., CT use) carries real risks and the benefits of treatment are uncertain.
authors.affiliation: Departments of Emergency Medicine and Health Policy, George Washington University, Washington, DC, USA. jesse.pines@gmail.com
authors.forename: Jesse M
authors.initials: JM
authors.lastname: Pines
authors.forename: Adam L
authors.initials: AL
authors.lastname: Lessler
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Ward
authors.forename: D
authors.initials: D
authors.lastname: Mark Courtney
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D000792:Angiography / Q000379:methods; D003661:Decision Support Techniques; D042241:Early Diagnosis; D004635:Emergency Medicine / Q000379:methods; D004636:Emergency Service, Hospital / Q000592:standards* / Q000639:trends; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000627:therapeutic use; D017052:Hospital Mortality; D006801:Humans; D008390:Markov Chains; D010690:Phlebography / Q000379:methods; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality*; D018570:Risk Assessment / Q000379:methods*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015996:Survival Rate; D015912:Thrombolytic Therapy / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D014481:United States
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D