system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All of the following are causes of primary headache EXCEPT:
assistant
The correct answer is  Ans. (d) SinusitisRef: Harrison 18th edition,chapter 14Primary HeadacheSecondary HeadacheType %Type %Tension -Type 69Systemic infection 63Migraine 16Head injury 4Idiopathic stabbing 2Vascular disorders 1Extertional 1Subarachnoid hemorrhage <1Cluster 0.1Brain tumor 0.1