title: ED patient estimation of blood loss.
abstract: OBJECTIVE
  Emergency department (ED) patients frequently estimate blood loss. How such information should guide evaluation and management, however, is unclear. The objective of this study was to examine ED patient accuracy in estimating blood loss on different surfaces.
  
  
  METHODS
  A convenience sample of 100 ED patients were asked to estimate the amount of moulage blood present in 4 scenarios: 178 mL spilled in a baking sheet on the floor; 5 mL in 2.5 mL of mucous in a tissue; 119 mL on a t-shirt; and 119 mL in a commode filled with water.
  
  
  RESULTS
  The mean percent error for all estimates was 412% with a range of 0% to 1080%. Estimates were within 100% of the actual amount 44% of the time. Eleven percent of assessments were correct and 70% were overestimates.
  
  
  CONCLUSIONS
  Emergency department patients do not estimate blood loss well in a variety of scenarios, erring on the side of overestimation.
authors.affiliation: Division of Emergency Medicine, University of Washington Medical Center, Box 356123, Seattle, WA 98195, USA. strote@u.washington.edu
authors.forename: Jared
authors.initials: J
authors.lastname: Strote
authors.forename: Monique
authors.initials: M
authors.lastname: Mayo
authors.forename: David
authors.initials: D
authors.lastname: Townes
mesh_terms: D004636:Emergency Service, Hospital; D006470:Hemorrhage / Q000175:diagnosis*; D006801:Humans; D011446:Prospective Studies