A short-cut review was carried out to determine whether the International Normalised Ratio (INR) value was a predictor of the risk of intracranial haemorrhage in patients taking warfarin after head injury. 796 papers were found using the reported search, of which eighteen were directly relevant. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses are shown in the accompanying table. It is concluded that level of the INR correlates poorly with the risk of haemorrhage and that the risk of haemorrhage remains significant even in patients with a sub-therapeutic INR.