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Table 1 Input parameter base-case values, plausible ranges and distributions

From: Vancomycin-resistant enterococci (VRE) screening and isolation in the general medicine ward: a cost-effectiveness analysis

Variable Base-case value Range Range Type Standard Error Distribution Source
VRE-Related Parameters
 Beta, basic reproductive number 1.32 1.03–1.46 Full 0.12 Gamma Satilmis 2016 [13]
 VRE prevalence, general 0.023 0–0.18 Full 0.001 Beta Williams 2015 [14]
 VRE prevalence, high-risk patients 0.092 0–0.36 Plausible 0.002 Beta Conly 2001 [15]
 LOS | without VRE infection, days 3 1.0–6.0 Full (IQR) 0.38 Gamma Johnstone 2018 [2]
 LOS | other VRE infection, days 6 1.0–6.0 Full (IQR) 0.77 Gamma Assumption; Johnstone 2018 [2]
 LOS | VRE-bacteremia, days 39 22.0–81.0 Full (IQR) 4.97 Gamma Johnstone 2018 [2]
Screening Parameters
 Sensitivity, rectal swab 0.991 0.95–1.00 Full 0.02 Beta Stamper 2010 [16]
 Specificity, rectal swab 0.949 0.92–0.97 Full 0.01 Beta Stamper 2010 [16]
 Effectiveness of isolation 1.00 0.75–1.00 Plausible   Assumption
 Discount rate, annual 0.015 0–0.03 Full CADTH 2017 [11]
Patient Parameters and Transition Probabilities
 Average age high-risk, years 61 1.15 Normal Johnstone 2018 [2]
 Probability infected | colonised 0.025 0.018–0.031 Plausible 0.003 Beta Williams 2015 [14]
 Probability bacteremia | infected 0.155 0.12–0.19 Plausible 0.02 Beta Saunders 2004 [17]
 Odds ratio bacteremia | infected, high-risk 1.55 0.56–4.29 Full 1.68 Lognormal Johnstone 2018 [2]
 Average days of treatment for BSI 14 11–18 Plausible 1.79 Gamma Daneman 2016 [18]
 Average days of treatment for other infections 7 5–9 Plausible 0.89 Gamma Daneman 2016 [18]
 Probability of death from VRE bacteremia, average, 14 days 0.37 0.27–0.46 Plausible 0.05 Beta Billington 2014 [19]
 Probability of death from VRE bacteremia, high-risk, 14 days 0.46 0.35–0.58 Plausible 0.06 Beta Linden 1996 [20]
 Number of room visits by all HCW, per day 24 18–30 Plausible 3.06 Normal Assumption
Costs
 Rectal swab screen 3.13 2.35–3.91 Plausible 0.40 Gamma Muto 2002 [9]
 Culture, positive test 21.36 16.02–26.7 Plausible 2.72 Gamma Muto 2002 [9]
 Culture, negative test 8.97 6.73–11.21 Plausible 1.14 Gamma Muto 2002 [9]
 PPE, per room visit 2.10 1.58–2.63 Plausible 0.27 Gamma Muto 2002 [9]
 Nurse time, per test 7.12 5.34–8.9 Plausible 0.91 Gamma Muto 2002 [9]
 Private room, daily 290 245–410 Full St. Joseph’s Hospital 2017 [21]
 Antibiotics, bacteremia, daily 524.22 393.17–655.28 Plausible 66.87 Gamma Nasr 2011 [22]
 Antibiotics, other infections, daily 35.8 26.85–44.75 Plausible 4.57 Gamma Nasr 2011 [22]
Utilities
 VRE bacteremia 0.56 0.51–0.61 Full 0.023 Beta Lee 2010 [23]
 Other local infections (UTI) 0.60 0.58–0.62 Full 0.01 Beta Haran 2005 [24]
 Inpatient 0.642 0.54–0.74 Full 0.05 Beta Tengs, 2000 [25]; Selai 1995 [26]
 Mild depression, no treatment 0.88 0.84–0.92 Full 0.02 Beta Revicki 1997 [27]
 Well, chronic conditions, recovered from previous VRE-related infection 0.86 0.34–0.89 Full 0.15 Beta Mittmann 1999 [28]
 Well, chronic conditions, no previous VRE-related infection 0.93 0.88–0.94 Full 0.083 Beta Mittmann 1999 [28]
  1. BSI bloodstream infection, CADTH Canadian Agency for Drugs and Technology in Health, HCW healthcare workers, IQR interquartile range, LOS length of stay, PPE personal protective equipment, UTI urinary tract infection, VRE vancomycin-resistant enterococcus