Table 2

 Management and outcomes of 3132 patients with acute headache in study of computed tomography for diagnosis of subarachnoid haemorrhage

OutcomeNo (%) of patients (n=3132)
Diagnostic procedures:
 Computed tomography ≤6 hours after headache onset953 (30.4)
 Lumbar puncture1546 (49.4)
 Computed tomography angiogram229 (7.3)
 Traditional angiogram75 (2.4)
 Magnetic resonance imaging angiogram13 (0.4)
Final diagnosis:
 Benign headache1750 (55.9)
 Migraine629 (20.1)
 Subarachnoid haemorrhage240 (7.7)
 Viral illness90 (2.9)
 Acute ischaemic stroke/transient ischaemic attack65 (2.1)
 Postcoital headache55 (1.8)
 Sinusitis36 (1.1)
 Syncope33 (1.1)
 Neck strain13 (0.4)
 Brain tumour with mass effect9 (0.3)
 Subdural haematoma9 (0.3)
 Intracerebral haemorrhage8 (0.3)
 Hypoglycaemia4 (0.1)
 Weakness—not determined4 (0.1)
 Bacterial meningitis1 (0.03)
 Other benign cause*186 (5.9)
Admitted to hospital345 (11.0)

*No patients were admitted to hospital or had diagnosis with any risk of important morbidity or mortality.