Longitudinal proxy measurements in multiple sclerosis: patient-proxy agreement on the impact of MS on daily life over a period of two years

Femke AH van der Linden^{* 1,2} , Jolijn J Kragt¹ , Margarethe van Bon¹ , Martin Klein² , Alan J Thompson⁴ , Henk M van der Ploeg² , Chris H Polman¹ and Bernard MJ Uitdehaag^{* 1,3}

¹Department of Neurology, VU University Medical Centre, Amsterdam, The Netherlands

²Medical Psychology, VU University Medical Centre, Amsterdam, The Netherlands

³Clinical Epidemiology and Biostatistics, VU University Medical Centre, Amsterdam, The Netherlands

⁴Neurological Outcome Measures Unit, Institute of Neurology, London, UK