1. A brief diagnostic screen for cluster headache: Creation and initial validation of the Erwin Test for Cluster Headache

2. Cluster headache is one of the most intensely painful human conditions: Results from the International Cluster Headache Questionnaire

3. Cluster headache epidemiology including pediatric onset, sex, and ICHD criteria: Results from the International Cluster Headache Questionnaire

4. Effectiveness of Oxygen and Other Acute Treatments for Cluster Headache: Results From the Cluster Headache Questionnaire, an International Survey