1. Neurology Department, Hospital Privado de Braga, 4715-196 Braga, Portugal
2. Neurology Department, Hospital Senhora da Oliveira de Guimarães, 4835-044 Guimarães, Portugal
3. School of Health Sciences, Universidade do Minho, 4710-057 Braga, Portugal
4. Neurology Department, Hospital de Braga, 4710-243 Braga, Portugal
5. Novartis Farma SA, 2740-255 Porto Salvo, Portugal
6. Department of Mathematics and Applications, Universidade do Minho, 4800-058 Guimarães, Portugal