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. 2009 Mar 11;13(2):R35. doi: 10.1186/cc7744

Table 1.

Parameter estimates used in the model

Parameters Baseline estimate Variation (SEM) Distribution Source Level of evidence
Infection-related events:
 Probability of CR-BSI Modeled in stepwise incrementsa Beta Database 1
 RR mortality (CR-BSI) 1.06 0.18 Log normal [1] 2
 Extra days in the ICU 2.41 0.83 Log normal [22] 2
 Extra days on hospital ward 7.54 1.81 Log normal

Effectiveness A-CVCs (RR):
 SPC 0.54 0.62 Log transformed normal [21] 1 +
 CH/SSD (ext) 0.66 0.17
 CH/SSD (int/ext) 0.70 0.43
 MR 0.39 0.43

Baseline probabilities of mortality:
 ICU mortality 0.098 0.002 Beta Dataset 2
 Hospital mortality 0.069 0.001 Beta Dataset 2
 Annual mortality post discharge Year 1 0.050 0.002 Beta [24] 2
Years 2 to 3 0.027 0.002
Years 4 to 5 0.028 0.002
Years 6 to 10 0.037 0.003
Years 11 to 15 0.042 0.003
 Underlying annual mortality 45 to 64 years 0.004 - NA [25] 1
65 to 84 years 0.030 -
85 + years 0.140 -

Utilities:
 Utility ICU 0.66 0.27 Beta [28] 3
 Utilities population norms 50 to 59 years 0.80 0.22 Beta [27] 3
60 to 69 years 0.79 0.19
70 to 79 years 0.75 0.25
80 + years 0.66 0.29

Costs, 2006 AUD:
 ICU bed day 3,021 - NA [31] 4
 Hospital bed day 843 - NA [32] 3
 Diagnostics CR-BSI 101.70 - NA Database 1
 Treatment CR-BSI 591.30 - NA Database 1
 Additional cost per catheter SPC 22.36 - NA Database 1
CH/SSD (ext) 11.64 -
CH/SSD (int/ext) 41.35 -
MR 59.36 -

aAvailable on request from the authors.

A-CVCs, antimicrobial central venous catheters; CH/SSD, chlorhexidine silver sulfadiazine; CR-BSI, catheter related bloodstream infection; ICU, intensive care unit; int/ext, internally and externally coated; MR, minocycline and rifampicin; RR, relative risk; SPC, silver, platinum and carbon.