ManousakiDRichardsJB. Vitamin D deficiency is an etiological factor for MS – Yes. Mult Scler2019; 25: 637–638.
2.
Langer-GouldALucasRM. Vitamin D deficiency is an etiological factor for MS – No. Mult Scler2019; 25: 639–641.
3.
RothmanKJGreenlandSPooleCet al. Causation and causal inference. In: RothmanKJGreenlandSLashTL (eds) Modern epidemiology. 3rd ed.Philadelphia, PA: Lippincott Williams & Wilkins, 2008, pp. 5–31.
4.
HillAB.The environment and disease: Association or causation?Proc R Soc Med1965; 58: 295–300.
5.
WeissNS.Can the ‘specificity’ of an association be rehabilitated as a basis for supporting a causal hypothesis?Epidemiology2002; 13: 6–8.
6.
RamagopalanSVMaugeriNJHandunnetthiLet al. Expression of the multiple sclerosis-associated MHC class II Allele HLA-DRB1*1501 is regulated by vitamin D. PLoS Genet2009; 5: e1000369.
7.
AscherioAMungerKLSimonKC.Vitamin D and multiple sclerosis. Lancet Neurol2010; 9: 599–612.
8.
HewisonM.Vitamin D and innate and adaptive immunity. Vitam Horm2011; 86: 23–62.
9.
WangYZhuJDeLucaHF.Where is the vitamin D receptor?Arch Biochem Biophys2012; 523: 123–133.
10.
HayesCE.Vitamin D: A natural inhibitor of multiple sclerosis. Proc Nutr Soc2000; 59: 531–535.
11.
HarroudARichardsJB.Mendelian randomization in multiple sclerosis: A causal role for vitamin D and obesity?Mult Scler2018; 24: 80–85.
12.
AllmanPHAbanIBTiwariHKet al. An introduction to Mendelian randomization with applications in neurology. Mult Scler Relat Disord2018; 24: 72–78.