title: Subgroups within "nonspecific" low back pain.
authors.forename: Gordon
authors.initials: G
authors.lastname: Waddell
mesh_terms: D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology* / Q000523:psychology; D017410:Practice Guidelines as Topic; D012307:Risk Factors