Summary statistics for creatine kinase (CK) and troponin testing before and after intervention
| Before intervention (January–December 2018) | After intervention (January–December 2019) | |
| CK orders | ||
| Total orders (n=76 714) | 47 556 | 25 332 |
| Monthly orders | ||
| Mean±SD | 3963±276 | 2111±795* |
| Median (Q1, Q3) | 3905 (3809, 4147) | 1721 (1608, 2340) |
| Troponin orders | ||
| Total orders (n=115 722) | 52 506 | 51 691 |
| Monthly orders | ||
| Mean±SD | 4376±259 | 4308±124 |
| Median (Q1, Q3) | 4381 (4259, 4541) | 4319 (4217, 4368) |
| CK-to-troponin ratio† | ||
| Monthly CK orders/troponin orders | ||
| Mean±SD | 0.906±0.030 | 0.490±0.184* |
| Coupled tests‡ | ||
| Total (% of total CK orders) | 34 625 (72.81%) | 14 769 (58.30%)* |
| Consecutive CK tests | ||
| Monthly consecutive CK tests | ||
| Mean±SD | 1444±144 | 758±341* |
| Consecutive troponin tests§ | ||
| Monthly consecutive troponin tests | ||
| Mean±SD | 1950±158 | 1989±61 |
| CK orders by clinical units | ||
| Emergency | 20 804 (43.75%) | 6227 (24.58%)* |
| Cardiology¶ | 4127 (8.68%) | 3720 (14.68%)* |
| Intensive care** | 12 682 (26.67%) | 7539 (29.76%)* |
| All other units | 9943 (20.91%) | 7846 (30.97%)* |
| Troponin orders by clinical units | ||
| Emergency | 25 875 (49.28%) | 24 939 (48.25%)* |
| Cardiology¶ | 5169 (9.84%) | 5278 (10.21%) |
| Intensive care** | 11 268 (21.46%) | 11 447 (22.15%) |
| All other units | 10 194 (19.41%) | 10 027 (19.40%) |
Data are count (percentage) of each column unless noted as median (IQR).
*Significant at p<0.001.
†CK divided by troponin.
‡Simultaneously ordered CK and troponin tests.
§Two or more tests on the same patient <24 hours apart.
¶Summed counts from cardiology ward, cardiac intensive care and post-procedure unit.
**Summed counts from cardiovascular, general and neurological intensive care units.