1. Neurology Department, Headache Outaptient Clinic, Centro Hospitalar Universitário Lisboa Norte, Hospital de Santa Maria, 1649-028 Lisbon, Portugal
2. Hospital da Luz Headache Center, Neurology Department, Hospital da Luz, 1500-650 Lisbon, Portugal
3. Centro de Estudos Egas Moniz, Universidade de Lisboa, 1649-028 Lisbon, Portugal
4. Center for Interdisciplinary Research in Health, Universidade Católica Portuguesa, 1649-023 Lisbon, Portugal