Comparison of physician's, parent's and patient's global ratings made on linear or 21-circle visual analogue scales (VAS) in juvenile idiopathic arthritis (JIA) - Dalprà S; Verazza S; Ferrari C; Parodi A; Davì S; Schiappapietra B; Consolaro A; Filocamo G; Viola S; Martini A; Ravelli A (BMC, 2008)