Number of laboratories that participated in each therapeutic drug monitoring proficiency testing during 2015–2019
| Test substances | Year | %Change (2019-2nd vs 2015-1st) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2015 | 2016 | 2017 | 2018 | 2019 | |||||||
| 1st | 2nd | 1st | 2nd | 1st | 2nd | 1st | 2nd | 1st | 2nd | ||
| Acetaminophen | 6 | 5 | 5 | 5 | 6 | 6 | 6 | 6 | 6 | 6 | 0.0 |
| Amikacin | 6 | 5 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 0.0 |
| Carbamazepine | 51 | 47 | 44 | 41 | 42 | 42 | 41 | 40 | 39 | 38 | –25.5 |
| Digoxin | 73 | 70 | 67 | 66 | 70 | 69 | 65 | 62 | 60 | 59 | –19.2 |
| Gentamicin | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 4 | 5 | 5 | 0.0 |
| Lithium | 34 | 35 | 28 | 31 | 32 | 33 | 33 | 33 | 35 | 33 | –2.9 |
| Methotrexate | 17 | 17 | 15 | 15 | 17 | 17 | 19 | 19 | 19 | 18 | 5.9 |
| Phenobarbital | 34 | 32 | 31 | 28 | 29 | 29 | 27 | 27 | 24 | 22 | –35.3 |
| Phenytoin | 50 | 47 | 47 | 43 | 44 | 43 | 41 | 40 | 38 | 37 | –26.0 |
| Phenytoin, free | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0.0 |
| Salicylate | 4 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | –25.0 |
| Theophylline | 43 | 41 | 36 | 36 | 35 | 32 | 29 | 28 | 27 | 24 | –44.2 |
| Tobramycin | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 0.0 |
| Valproic acid | 90 | 90 | 86 | 82 | 85 | 85 | 85 | 84 | 84 | 84 | –6.7 |
| Valproic acid, free | 1 | 1 | 2 | 3 | 3 | 3 | 3 | 3 | 2 | 2 | 100.0 |
| Vancomycin | 57 | 59 | 63 | 62 | 66 | 67 | 71 | 70 | 70 | 74 | 29.8 |
| Cyclosporine | 47 | 48 | 48 | 46 | 48 | 47 | 47 | 48 | 50 | 52 | 10.6 |
| Everolimus | - | - | 8 | 8 | 8 | 8 | 10 | 10 | 11 | 12 | - |
| Sirolimus | 10 | 11 | 12 | 12 | 12 | 12 | 14 | 14 | 14 | 15 | 50.0 |
| Tacrolimus (FK506) | 57 | 59 | 60 | 61 | 66 | 65 | 67 | 68 | 72 | 73 | 28.1 |
| Total no. of institutions | 105 | 106 | 103 | 104 | 110 | 110 | 110 | 110 | 113 | 114 | 8.6 |