Main model outcomes of different troponin-supported assessment strategies
| Indicator | Strategy 1 (standard) | Strategy 2 (hsTnI) | Strategy 3 (hsTnI+LoD) | Strategy 4 (hsTnI+ADP) | Strategy 5 (hsTnI+LoD+ADP) | Strategy 6 (hsTnI+LoD+ADP+ direct rule- in) | |
| Short-stay unit admissions*, % | Mean (95% CI) | 65.3 (64.8 to 65.7) | 65.3 (64.8 to 65.7) | 60.4 (59.9 to 60.8) | 65.3 (64.8 to 65.7) | 60.4 (59.9 to 60.8) | 60.4 (59.9 to 60.8) |
| Incremental† (p value) | 0.0 (1.00) | −4.9 (<0.001) | 4.9 (<0.001) | −4.9 (<0.001) | 0.0 (1.00) | ||
| Ward admissions*, % | Mean (95% CI) | 49.7 (49.2 to 50.2) | 49.6 (49.1 to 50.1) | 47.4 (46.9 to 47.9) | 38.4 (37.9 to 38.9) | 37.1 (36.6 to 37.6) | 37.1 (36.6 to 37.6) |
| Incremental† (p value) | −0.1 (0.81) | −2.3 (<0.001) | −9.0 (<0.001) | −1.3 (<0.001) | 0.0 (1.00) | ||
| Overnight stays, % | Mean (95% CI) | 60.3 (59.8 to 60.8) | 42.0 (41.5 to 42.5) | 39.8 (39.3 to 40.3) | 24.4 (24.0 to 24.8) | 23.9 (23.5 to 24.3) | 24.1 (23.7 to 24.5) |
| Incremental† (p value) | −18.3 (<0.001) | −2.2 (<0.001) | −15.4 (<0.001) | −0.5 (0.08) | 0.2 (0.51) | ||
| Referral to ACS management, % | Mean (95% CI) | 32.4 (32.0–32.9) | 32.2 (31.8 to 32.7) | 30.9 (30.5 to 31.4) | 21.0 (20.6 to 21.4) | 20.7 (20.3 to 21.1) | 20.9 (20.5 to 21.3) |
| Incremental† (p value) | −0.2 (0.56) | −1.3 (<0.001) | −9.9 (<0.001) | −0.3 (0.26) | 0.3 (0.37) | ||
| Length of stay, hours | Mean (95% CI) | 34.0 (33.6 to 34.4) | 27.8 (27.4 to 28.2) | 26.8 (26.4 to 27.3) | 20.4 (20.0 to 20.9) | 20.1 (19.6 to 20.5) | 20.4 (19.9 to 20.8) |
| Incremental† (p value) | −6.2 (<0.001) | −1.0 (0.002) | −6.4 (<0.001) | −0.4 (0.23) | 0.3 (0.33) | ||
| Diagnostic accuracy (E), % | Mean (95% CI) | 90.0 (89.7 to 90.3) | 90.0 (89.7 to 90.3) | 90.5 (90.2 to 90.8) | 93.6 (93.4 to 93.8) | 93.7 (93.5 to 93.9) | 94 (93.7 to 94.2) |
| Incremental† (p value) | 0.0 (0.86) | 0.4 (0.04) | 3.1 (<0.001) | 0.1 (0.54) | 0.3 (0.13) | ||
| Index costs per patient, $ | Mean (95% CI) | 3029 (3001 to 3058) | 2923 (2894 to 2952) | 2846 (2816 to 2875) | 2621 (2592 to 2649) | 2568 (2539 to 2596) | 2582 (2553 to 2610) |
| Incremental† (p value) | −106 (<0.001) | −77 (<0.001) | −225 (<0.001) | −53 (0.01) | 14 (0.51) | ||
| Follow-up costs per patient, $ | Mean (95% CI) | 238 (225 to 250) | 211 (199 to 223) | 211 (199 to 223) | 213 (201 to 225) | 213 (201 to 225) | 195 (183 to 206) |
| Incremental† (p value) | −26 (0.003) | 0 (1.00) | 2 (0.82) | 0 (1.00) | −18 (0.03) | ||
| Total costs per patient (C), $ | Mean (95% CI) | 3267 (3236 to 3297) | 3134 (3103 to 3165) | 3057 (3026 to 3088) | 2834 (2804 to 2864) | 2781 (2751 to 2811) | 2776 (2746 to 2807) |
| Incremental† (p value) | −133 (<0.001) | −77 (0.001) | −223 (<0.001) | −53 (0.02) | −5 (0.83) | ||
All stated costs are in A$. (E) and (C) used as main measures of outcome.
*Patients could be admitted to the short-stay unit before being referred to inpatient ward; numbers may not sum up to 100%.
†Incremental values compared with next best alternative to the left.
ACS, acute coronary syndrome; ADP, accelerated diagnostic protocol; hsTnI, highly sensitive cardiac troponin I; LoD, limit of detection.