Impact of the Arrival on the French Market of New First Line Oral Treatments on the Delay Between MS Onset and First Disease Modifying Treatment (DMTs) Administration

Delay between MS onset and introduction of first line DMT : time between date of MS onset ( the first demyelinating neurological events clinically defined) and date of the introduction of the first-line oral DMT (Interferons, Glatiramer Acetate, Dimethyl Fumarate and Teriflunomide)

For all cases of multiple sclerosis residence's places of each patient were geolocalized with a Geographic Information System (ARCGIS 10.2) and assigned to an IRIS, IRIS (Ilots Regroupés pour l'Information Statistique) is the smallest French geographic unit for which census data are available and EDI score was calculated for each IRIS. In order to attribute a social deprivation score to the IRIS, we used the French EDI (European Deprivation Index). EDI stands as a continuous variable but EDI will be used as a categorical variable in order to increase the comparability with others studies, so EDI is distributed into quintiles calculated at the French level.