title: [Erratum to: Opioids in chronic low back pain. A systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks duration].
abstract: In Infobox 1 (Excluded with reason), p. 9, two reference numbers are missing. Item 2 (Gordon et al.): [34] Item 4 (Yarlas et al.): All data published by [39]
authors.affiliation: Schmerz-Tagesklinik und -Ambulanz, Universitätsmedizin Göttingen, Göttingen, Deutschland.
authors.forename: F
authors.initials: F
authors.lastname: Petzke
authors.forename: P
authors.initials: P
authors.lastname: Welsch
authors.forename: P
authors.initials: P
authors.lastname: Klose
authors.forename: R
authors.initials: R
authors.lastname: Schaefert
authors.forename: C
authors.initials: C
authors.lastname: Sommer
authors.forename: W
authors.initials: W
authors.lastname: Häuser