RT Journal Article SR Electronic T1 Moderate quality evidence that compared to advice to rest in bed, advice to remain active provides small improvements in pain and functional status in people with acute low back pain JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 171 OP 172 DO 10.1136/ebm1132 VO 15 IS 6 A1 Bart Koes YR 2010 UL http://ebm.bmj.com/content/15/6/171.abstract AB