Table 4 Use of D-dimer in patients undergoing CTPA
From: Finding an alternative diagnosis does not justify increased use of CT-pulmonary angiography
Pre-test probability | n | D-dimer not performed, % (CTPA positive %) | D-dimer performed | |
|---|---|---|---|---|
Negative D-dimer, % (CTPA positive, %) | Positive D-dimer, % (CTPA positive, %) | |||
Low | ||||
2000 | 19 | 100.0 (100) | - | - |
2005 | 94 | 78.7 (6.8) | 4.3 (0) | 17 (0) |
2008 | 113 | 68.1 (16.9) | 7 (0) | 24.8 (7.1) |
Intermediate | ||||
2000 | 52 | 98.1 (33.3) | 1.9 (0) | - |
2005 | 285 | 81.0 (23.8) | 1.8 (0) | 17.2 (24.5) |
2008 | 260 | 79.2 (15.5) | 4.6 (0) | 16.2 (21.4) |
High | ||||
2000 | 3 | 100.0 (66.7) | - | - |
2005 | 4 | 75.0 (33.3) | - | 25 (100) |
2008 | 20 | 85.0 (23.5) | - | 15 (0) |