Author Affiliations: Department of Neurology, Institute for Neurological Research Dr Raúl Carrea, Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia, Buenos Aires, Argentina.
The self-controlled case series (SCCS) method was specifically developed to study the association between vaccines and different events, such as MS relapses.1 Since it was first introduced in 1995, more than 40 studies have been published using this method to assess the effect of immunizations on a variety of outcomes.2
Farez MF, Correale J. Methodological Issues With the Risk of Relapse Study in Patients With Multiple Sclerosis After Yellow Fever Vaccination—Reply. Arch Neurol. 2012;69(1):144-145. doi:10.1001/archneurol.2011.1521