Editors' Pick Onset of progressive phase is an age-dependent clinical milestone in multiple sclerosis. Tutuncu M, Tang J, Zeid N A, Kale N, Crusan DJ, Atkinson EJ, Siva A, Pittock SJ, Pirko I, Keegan MB, et al. Mult Scler. 2012 Jun 26. PMID: 22736750. Abstract CommentRecommendBookmarkWatch