Patients
Records of patients who presented to the ED of a large Australian
metropolitan general hospital within twelve calendar months who
underwent D-dimer testing were reviewed. Patients were included if they
were over 16 years of age and had a D-dimer assay for suspected PE.
Patients who had DD testing for suspected deep vein thrombosis (DVT)
without PE, or for explicitly other reasons – such as assessment for
disseminated intravascular coagulation after snake bites – were
excluded.
Patient records were reviewed to re-calculate a pre-test probability
based on the Revised Geneva Score (RGS – as summarised by Wong et
al9). While the Wells score is more widely used and is
well validated10, it is difficult to calculate post
hoc, especially as a major component of this score – that PE is the
most likely diagnosis – is subjective. RGS, by contrast, uses objective
and quantifiable measures, as summarised in Table 1. Both clinical
scoring systems are reported to have similar accuracy9,
11.