Rapid Differential Diagnosis of Non-Traumatic Headache in the Emergency Department: A Systematic Review and Evidence-Based Diagnostic Algorithm for Identifying Life-Threatening Secondary Headaches

Background

Non-traumatic headache accounts for a substantial minority of emergency department (ED) attendances. Only a small proportion of these presentations arise from a life-threatening secondary cause, but the consequences of a missed diagnosis are severe. Guidance concentrates heavily on subarachnoid haemorrhage, and it is unclear how the wider differential should be structured at the bedside.