Headache is the commonest human symptom and it is also how subarachnoid haemorrhage, giant cell arteritis and bacterial meningitis introduce themselves. Every patient here goes through the same three steps in the same order: screen for red flags, name the headache, then act. Treating before you screen is the error this bench exists to break.
Step 1 — tick every SNOOP red flag this history contains
Ticking nothing is a legitimate answer — most headaches are primary. But a missed flag is the one that costs a patient their sight, their hearing or their life.