Table 4.

 Detailed description of four patients classified as low risk (Wells score ≤4 and negative point of care D-dimer test) but diagnosed as having pulmonary embolism by spiral computed tomography directly after referral

Patient No	Description	D-dimer test result
1	75 year old man, with acute onset of pain on inspiration, no shortness of breath. Wells score 1.5* (previous venous thromboembolism)	Negative
2	25 year old woman with acute onset of pain on inspiration and shortness of breath. Patient used oral contraceptives. Wells score 0*	Negative
3	80 year old woman with subacute progressive shortness of breath after a flight. Wells score 3* (previous venous thromboembolism and immobilisation)	Negative
4	30 year old woman with acute onset of pain on inspiration but no shortness of breath. Patient used oral contraceptives. Wells score 3* (pulmonary embolism most likely diagnosis)	Negative

*As scored by primary care doctor.

†Not interpretable; to simplify results were analysed as a positive test result.