1. Low back pain (chronic);van Tulder;Clin Evid,2006
2. The epidemiology of spinal disorders;Andersson,1997
3. Back pain and sciatica;Frymoyer;N Engl J Med,1988
4. Who will develop chronic pain and why?;Macfarlane,2006
5. Diagnosis and treatment of low back pain;Koes;BMJ,2006