00410nas a2200145   4500000000100000008004100001100001600042700001600058700001700074700002100091245012700112300001200239490000700251050000600258       2009                            d1 aFerreira P.1 aHerbert Rob1 aLatimer Jane1 aFerreira Manuela00aPeople with low back pain typically need to feel 'much better' to consider intervention worthwhile: an observational study  a123-7. 0 v55  aY