[1] Univ Porto, Fac Med, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[2] Ctr Hosp Sao Joao, Dept Internal Med, Oporto, Portugal
[3] CINTESIS Ctr Hlth Technol & Serv Res, Oporto, Portugal
[4] Ctr Hosp Sao Joao, Dept Neurosurg, Oporto, Portugal
[5] Univ Porto, Fac Med, Dept Clin Neurosci & Mental Hlth, Rua Campo Alegre 823, P-4100 Oporto, Portugal