A Comparative-Effectiveness Analysis Applying a 3 Way Propensity Matching to Real-World Data From MSBase Registry in Preparation for a Cost Effectiveness Model: Patients Switching Within Firstline Agents or to Natalizumab or Fingolimod in Active RRMS

7th Joint European-Committee-for-Treatment-and-Research-in-Multiple-Sclerosis (ECTRIMS)-Americas-Committee-for-Treatment-and-Research-in-Multiple-Sclerosis (ACTRIMS) -- OCT 25-28, 2017 -- Paris, FRANCE