Symptomatic intracranial haemorrhage

Method

Proportion of patients with intracranial blood on follow-up imaging accompanied by neurological deterioration meeting the trial stated definition, commonly a rise of 4 or more points on the NIH Stroke Scale, or the ECASS-II, ECASS-III, SITS-MOST or NINDS criteria. The criterion set applied is recorded on the edge; the sets are not interchangeable.

The method is part of the endpoint identity. Studies measuring the same quantity by a different method are held as separate endpoints.

Notes

The near-miss is any-intracranial-haemorrhage incidence, which counts radiographic blood regardless of clinical effect and runs three to six times higher because most haemorrhagic transformation after infarction is asymptomatic. Pooling the two dilutes the exact harm signal that reperfusion decisions turn on. The choice of criterion set alone shifts reported rates roughly two-fold, which is why it is mandatory. Distinct from CAT:outcome/nih-stroke-scale-score, which supplies the deterioration threshold but is a continuous severity score rather than an event.