The meta-analysis by Hofman et al (this issue pp416–22)1 opens again a running argument in both neurosurgery and neuroradiology. The argument is not unimportant: the outcome could affect the outlook for some people with an apparently mild head injury and have a significant impact on costs and workloads. The repercussions of these effects are on different people and it is unsurprising to find the merits of radiography usually being emphasised by surgeons and its demerits by radiologists. Two of Hofman's coauthors are radiologists and the third is an epidemiologist.

Their most valuable contribution is to refute the claim, oft repeated but not concordant with everyday experience, that demonstration of a skull fracture increases the risk of significant intracranial haemorrhage by a factor of 40. Their meta-analysis confirms an increased risk, …