Table 1. Probabilities and Costs Based on the Literature and Linked Data Sources .

Probability and costs	Value	Rangea	Source
Probability
Complete prehospital troponin and risk assessment	0.792	0.50-0.90	Stopyra et al,8 2021
Patients with ACS with an initial prehospital positive troponin test result	0.352	0.20-0.50	Neumann et al,19 2016
Patients with suspected ACS avoiding a short stay or hospital admission	0.123	0.00-0.15	Stopyra et al,8 2021; Chew et al,20 2019
Patients with chest pain undergoing a suspected ACS pathwayb	0.747	0.50-0.90	Chew et al,20 2019; AV data set
Diagnosed with MI	0.062	0.04-0.10	AV data set
Nearest center not capable of revascularization	0.323	0.15-0.50	AV data set
Suspected ACS case classified as low risk by prehospital HEART score with resolution of pain and normal observations	0.207	0.10-0.40	Backus et al,21 2013; AV data set
Chest pain case classified as low or very-low risk by prehospital ECAMM score with normal troponin level and resolution of pain	0.412	0.20-0.50	Dawson et al,18 2022; AV data set
Annual proportion of point-of-care devices requiring repairs or replacement following warranty expirationc	0.050	0.00-0.10	Author consensus
Estimated costs (Australian $)
Attendance outcome and disposition
Nonrevascularization center
ED discharge	2448	Fixed	AV data set
Short stay discharge	4145	Fixed	AV data set
Admission (non-ACS)	10 098	Fixed	AV data set
Transfer (ACS)	24 195	Fixed	AV data set
Not suspected ACS	5519	Fixed	AV data set
Revascularization center
ED discharge	2275	Fixed	AV data set
Short stay discharge	4069	Fixed	AV data set
Admission (non-ACS)	11 292	Fixed	AV data set
Admission (ACS)	16 512	Fixed	AV data set
Not suspected ACS	5974	Fixed	AV data set
Low-risk classification and not transported to the hospital	685	Fixed	AV data set
Point-of-care troponin device costs
iStat analyzers (annual)d	972 000	Fixed	Abbott Point of Care
iStat simulators (annual)d	21 500	Fixed	Abbott Point of Care
hsTn cartridge (cost per attendance)e	16	Fixed	Abbott Point of Care
Paramedic education costs (annual)f	502 380	Fixed	Australian Government
Virtual ED costs
24/7 ED consultant physician (annual)g	1 921 303	Fixed	AMA Victoria
24/7 Administration staff (annual)h	311 784	Fixed	Victoria State Government
Infrastructure and operational (annual)	100 000	Fixed	Author consensus

Abbreviations: ACS, acute coronary syndrome; AV, Ambulance Victoria; ECAMM, Early Chest Pain Admission Mortality and Myocardial Infarction; ED, emergency department; HEART, history, electrocardiogram, age, risk factors, and troponin; hsTn, high-sensitivity troponin; MI, myocardial infarction.

^a Range indicates limits of β-distribution for the probabilities used in the multivariable probabilistic sensitivity analyses.

^b Rate of MI in the AV data set of undifferentiated chest pain (6.2% MI) divided by the rate of MI in the Rapid Assessment of Possible Acute Coronary Syndrome in the Emergency Department With High-Sensitivity Troponin T Study cohort with suspected ACS (8.3% rule-in MI).

^c Annual proportion of point-of-care devices requiring repairs or replacement following a 2-year warranty calculated by multiplying the probability value by total annual cost of fleet analyzers and simulators.

^d iStat analyzer and simulator costs assume a 5-year expected device lifetime for a statewide ambulance fleet of 810 response teams with 215 branches requiring 1 analyzer per team and 1 simulator per branch.

^e High-sensitivity troponin cartridge cost per attendance accounts for an estimated 10% of cartridges being discarded due to storage issues, mishandling, device errors, or other unforeseen events.

^f Paramedic education costs estimated at an additional 3 hours annually for 6000 staff at a rate of $27.91/h (midpoint of the advanced life support paramedic pay scale), with additional education occurring during regular teaching periods (40 hours per year).

^g Virtual ED consultant physician annual cost estimated based on hourly rates for a year 3 consultant ED physician staffing a single statewide virtual ED 24 hours per day 7 days per week (accounting for out-of-hours shift penalties).

^h Annual cost estimated based on weekly rates and out-of-hours allowances for public hospital administration workers (grade 1, level 3).