title: Impact of a Risk Calculator on Risk Perception and Surgical Decision Making: A Randomized Trial.
abstract: OBJECTIVE
  The aim of this study was to determine whether exposure to data from a risk calculator influences surgeons' assessments of risk and in turn, their decisions to operate.
  
  
  BACKGROUND
  Little is known about how risk calculators inform clinical judgment and decision-making.
  
  
  METHODS
  We asked a national sample of surgeons to assess the risks (probability of serious complications or death) and benefits (recovery) of operative and nonoperative management and to rate their likelihood of recommending an operation (5-point scale) for 4 detailed clinical vignettes wherein the best treatment strategy was uncertain. Surgeons were randomized to the clinical vignettes alone (control group; n = 384) or supplemented by data from a risk calculator (risk calculator group; n = 395). We compared surgeons' judgments and decisions between the groups.
  
  
  RESULTS
  Surgeons exposed to the risk calculator judged levels of operative risk that more closely approximated the risk calculator value (RCV) compared with surgeons in the control group [mesenteric ischemia: 43.7% vs 64.6%, P < 0.001 (RCV = 25%); gastrointestinal bleed: 47.7% vs 53.4%, P < 0.001 (RCV = 38%); small bowel obstruction: 13.6% vs 17.5%, P < 0.001 (RCV = 14%); appendicitis: 13.4% vs 24.4%, P < 0.001 (RCV = 5%)]. Surgeons exposed to the risk calculator also varied less in their assessment of operative risk (standard deviations: mesenteric ischemia 20.2% vs 23.2%, P = 0.01; gastrointestinal bleed 17.4% vs 24.1%, P < 0.001; small bowel obstruction 10.6% vs 14.9%, P < 0.001; appendicitis 15.2% vs 21.8%, P < 0.001). However, averaged across the 4 vignettes, the 2 groups did not differ in their reported likelihood of recommending an operation (mean 3.7 vs 3.7, P = 0.76).
  
  
  CONCLUSIONS
  Exposure to risk calculator data leads to less varied and more accurate judgments of operative risk among surgeons, and thus may help inform discussions of treatment options between surgeons and patients. Interestingly, it did not alter their reported likelihood of recommending an operation.
authors.affiliation: *Department of Surgery, UCLA David Geffen School of Medicine, Los Angeles, CA †VA Greater Los Angeles Healthcare System, Los Angeles, CA ‡Department of Health Policy and Management, UCLA Fielding School of Public Health, Los Angeles, CA §Department of Medicine, UCLA David Geffen School of Medicine, Los Angeles, CA ||RAND Corporation, Los Angeles, CA ¶UCLA Anderson School of Management, Los Angeles, CA #Department of Psychology, UCLA College of Letters and Sciences, Los Angeles, CA.
authors.forename: Greg D
authors.initials: GD
authors.lastname: Sacks
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Dawes
authors.forename: Susan L
authors.initials: SL
authors.lastname: Ettner
authors.forename: Robert H
authors.initials: RH
authors.lastname: Brook
authors.forename: Craig R
authors.initials: CR
authors.lastname: Fox
authors.forename: Marcia M
authors.initials: MM
authors.lastname: Russell
authors.forename: Clifford Y
authors.initials: CY
authors.lastname: Ko
authors.forename: Melinda
authors.initials: M
authors.lastname: Maggard-Gibbons
mesh_terms: D000328:Adult; D001291:Attitude of Health Personnel; D003657:Decision Making; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D018570:Risk Assessment / Q000379:methods*; D066231:Surgeons / Q000523:psychology*; D013514:Surgical Procedures, Operative / Q000009:adverse effects* / Q000401:mortality*; D014481:United States