title: Impact of adding therapeutic recommendations to risk assessments from a prediction model for postoperative nausea and vomiting.
abstract: BACKGROUND
  In a large cluster-randomized trial on the impact of a prediction model, presenting the calculated risk of postoperative nausea and vomiting (PONV) on-screen (assistive approach) increased the administration of risk-dependent PONV prophylaxis by anaesthetists. This change in therapeutic decision-making did not improve the patient outcome; that is, the incidence of PONV. The present study aimed to quantify the effects of adding a specific therapeutic recommendation to the predicted risk (directive approach) on PONV prophylaxis decision-making and the incidence of PONV.
  
  
  METHODS
  A prospective before-after study was conducted in 1483 elective surgical inpatients. The before-period included care-as-usual and the after-period included the directive risk-based (intervention) strategy. Risk-dependent effects on the administered number of prophylactic antiemetics and incidence of PONV were analysed by mixed-effects regression analysis.
  
  
  RESULTS
  During the intervention period anaesthetists administered 0.5 [95% confidence intervals (CIs): 0.4-0.6] more antiemetics for patients identified as being at greater risk of PONV. This directive approach led to a reduction in PONV [odds ratio (OR): 0.60, 95% CI: 0.43-0.83], with an even greater reduction in PONV in high-risk patients (OR: 0.45, 95% CI: 0.28-0.72).
  
  
  CONCLUSIONS
  Anaesthetists administered more prophylactic antiemetics when a directive approach was used for risk-tailored intervention compared with care-as-usual. In contrast to the previously studied assistive approach, the increase in PONV prophylaxis now resulted in a lower PONV incidence, particularly in high-risk patients. When one aims for a truly 'PONV-free hospital', a more liberal use of prophylactic antiemetics must be accepted and lower-risk thresholds should be set for the actionable recommendations.
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, PO Box 85500, Mail stop F.06.149, Utrecht, 3508 GA, The Netherlands t.kappen@umcutrecht.nl.
authors.forename: T H
authors.initials: TH
authors.lastname: Kappen
authors.affiliation: Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, PO Box 85500, Mail stop STR.6.131, Utrecht, 3508 GA, The Netherlands Department of Public Health, Erasmus Medical Center, PO Box 1738, Rotterdam, 3000 DR, The Netherlands.
authors.forename: Y
authors.initials: Y
authors.lastname: Vergouwe
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, PO Box 85500, Mail stop F.06.149, Utrecht, 3508 GA, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: van Wolfswinkel
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, PO Box 85500, Mail stop F.06.149, Utrecht, 3508 GA, The Netherlands.
authors.forename: C J
authors.initials: CJ
authors.lastname: Kalkman
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, PO Box 85500, Mail stop F.06.149, Utrecht, 3508 GA, The Netherlands Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, PO Box 85500, Mail stop STR.6.131, Utrecht, 3508 GA, The Netherlands.
authors.forename: K G M
authors.initials: KG
authors.lastname: Moons
authors.affiliation: Division of Anaesthesiology, Intensive Care and Emergency Medicine, University Medical Center Utrecht, PO Box 85500, Mail stop F.06.149, Utrecht, 3508 GA, The Netherlands.
authors.forename: W A
authors.initials: WA
authors.lastname: van Klei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000932:Antiemetics / Q000627:therapeutic use; D003661:Decision Support Techniques; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D020250:Postoperative Nausea and Vomiting / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D018570:Risk Assessment / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000932:Antiemetics
keywords: antiemetics; decision support techniques; drug therapy, computer-assisted; postoperative nausea and vomiting; postoperative nausea and vomiting/prevention and control; prognosis