title: Epidemiologic strategies to detect an exogenous cause of MS.
authors.affiliation: Department of Neurology, Mayo Clinic/Mayo Foundation, Rochester, USA.
authors.forename: B G
authors.initials: BG
authors.lastname: Weinshenker
mesh_terms: D016022:Case-Control Studies; D016000:Cluster Analysis; D015331:Cohort Studies; D004641:Emigration and Immigration; D006801:Humans; D015994:Incidence; D009103:Multiple Sclerosis / Q000453:epidemiology* / Q000209:etiology; D015995:Prevalence; D012307:Risk Factors