Table 1. Parameters used in the model.
Parameters | Estimate | Source | Ref | Level of evidence | |
Infection related events | |||||
Daily probability CR-BSI | Day 1–5 | 0.004 | database & Q–E study | [22] [21] | 1 |
Day 6–15 | 0.009 | ||||
Day 16–30 | 0.020 | ||||
RR mortality CR-BSI | 1.06 | Q–E study | [1] | 2 | |
Daily probability catheter removal | time varying | Q–E study | [21] | 2 | |
Baseline mortality (probabilities) | |||||
ICU | 0.098 | data linkage study | [24] | 2 | |
Hospital | 0.069 | ||||
Annual post-discharge | Year 1 | 0.050 | |||
Year 2–3 | 0.027 | ||||
Year 4–5 | 0.028 | ||||
Year 6–10 | 0.037 | ||||
Year 11–15 | 0.042 | ||||
Underlying annual mortality | 45–64 yrs | 0.004 | national statistics | [25] | 1 |
65–84 yrs | 0.030 | ||||
85+ yrs | 0.140 | ||||
Utilities | |||||
ICU | 0.66 | elicitation study (EQ-5D) | [26] | 3 | |
Population norms | 50–59 yrs | 0.80 | population based survey | [28] | 3 |
60–69 yrs | 0.79 | ||||
70–79 yrs | 0.75 | ||||
80+ yrs | 0.66 | ||||
Cost of CR-BSI | |||||
Extra days ICU | 2.41 | Q–E study | [23] | 2 | |
ICU bed-day (2006 AUD) | 3,021 | costing study | [30] | 4 | |
Extra days hospital | 7.54 | Q–E study | [23] | 2 | |
Hospital bed-day (2006 AUD) | 843 | prior economic evaluation | [31] | 3 | |
Diagnostics CR-BSI (2006 AUD) | 101.7 | health system database | - | 1 | |
Treatment CR-BSI (2006 AUD) | 591.3 | ||||
Effectiveness infection control (RR) | |||||
CH/SSD catheter | 0.66 | meta-analysis | [12] | 1+ | |
MR catheter | 0.39 | ||||
Bundle | 0.34 | Q–E study | [33] | 2 | |
Additional cost infection control (per catheter; 2006 AUD) | |||||
CH/SSD catheter | 11.64 | health system database | - | 1 | |
MR catheter | 59.36 | ||||
Bundle | unknown | - | - | 6 |
Abbreviations: s.e. standard error; CR-BSI catheter related bloodstream infection; ICU intensive care unit; Q–E quasi-experimental; AUD Australian dollar; ec. eval'n economic evaluation; CH/SSD chlorhexidine & silver sulfadiazine; (int/ext) internal & external coating; SPC silver, platinum & carbon; MR minocycline & rifampicin; popul'n population; per comm. personal communication; A-CVC antimicrobial central venous catheter; RR relative risk.