1. Department of Dermatology Hospital Universitario Central de Asturias, University of Oviedo Oviedo Spain
2. GRIDER, Investigation Group of Dermatology Asturias University of Oviedo Oviedo Spain
3. Research Methodology Group University Clinical Hospital of Santiago, Health Research Institute of Santiago de Compostela Santiago de Compostela Spain
4. Department of Dermatology Hospital Universitario Marqués de Valdecilla Santander Spain