Head of the Tremlett Lab and the Epidemiology in Multiple Sclerosis research program. Research interests include: the natural history of MS; prognosis and predictors of disease progression in MS; mortality; safety and effectiveness of the MS drugs; pharmacogenomics; MS epidemiology; incidence and prevalence of MS; life expectancy in MS; comorbidities and MS; pregnancy and MS; health administrative data; the MS prodrome; the gut microbiome.