RT Journal Article SR Electronic T1 Study boosts vitamin D–multiple sclerosis link JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E427 OP E428 DO 10.1503/cmaj.109-5145 VO 187 IS 14 A1 Carolyn Brown YR 2015 UL http://www.cmaj.ca/content/187/14/E427.abstract