[1] Oslo Univ Hosp, Rikshosp, Dept Radiol, Oslo, Norway
[2] Baerum Hosp, Dept Radiol, Drammen, Norway
[3] Oslo Univ Hosp, Clin Radiol & Nucl Med, Oslo, Norway
[4] Univ Oslo, Dept Psychol, Oslo, Norway
[5] Univ Oslo, Inst Clin Med, Fac Med, Oslo, Norway
[6] Oslo Univ Hosp, Oslo Ctr Biostat & Epidemiol, Res Support Serv, Oslo, Norway
[7] Oslo Metropolitan Univ, Fac Hlth Sci, Oslo, Norway
[8] Sorlandet Hosp, Dept Geriatr & Internal Med, Arendal, Norway
[9] Oslo Univ Hosp, Rikshosp, Dept Neurosurg, Oslo, Norway
[10] Oslo Univ Hosp, Dept Neurosurg, Rikshosp, PB Nydalen 4950, N-0424 Oslo, Norway