RT Journal Article SR Electronic T1 Fifty shades of grey: concussion complexities and constructive conclusions JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 492 OP 493 DO 10.1136/bjsports-2014-094284 VO 49 IS 8 A1 Patricios, Jonathan A1 Makdissi, Michael YR 2015 UL http://bjsm.bmj.com/content/49/8/492.abstract AB