title: Exercise reduces sick leave in patients with non-acute non-specific low back pain: a meta-analysis.
abstract: OBJECTIVE
  To investigate whether exercise alone or as a part of a multidisciplinary treatment reduces sick leave in patients with non-specific non-acute low back pain.
  
  
  METHODS
  A meta-analysis of randomized controlled trials was performed. A qualitative analysis of the sick leave results was performed applying pre-defined levels of evidence. In studies comparing exercise with usual care, pooled effect sizes were computed.
  
  
  RESULTS
  Fourteen trials were identified allowing 22 comparisons between treatments. The qualitative and the quantitative analysis showed strong evidence that exercise reduces sick days during the first follow-up year, the effect size (95% confidence interval) was -0.24 ( -0.36, -0.11). In a subgroup of studies on the treatment of severely disabled patients (> 90 sick days under usual care) the effect size was -0.30 (-0.42, -0.17). The effect size of the number of patients receiving a disability allowance was small and not significant.
  
  
  CONCLUSIONS
  The reviewed trials provide strong evidence that exercise significantly reduces sick days during the first follow-up year.
authors.affiliation: Research Department, Rehabilitation Centre Valens, Switzerland. j.kool@klinik-valens.ch
authors.forename: Jan
authors.initials: J
authors.lastname: Kool
authors.forename: Rob
authors.initials: R
authors.lastname: de Bie
authors.forename: Peter
authors.initials: P
authors.lastname: Oesch
authors.forename: Otto
authors.initials: O
authors.lastname: Knüsel
authors.forename: Piet
authors.initials: P
authors.lastname: van den Brandt
authors.forename: Stefan
authors.initials: S
authors.lastname: Bachmann
mesh_terms: D015444:Exercise; D006801:Humans; D017116:Low Back Pain / Q000534:rehabilitation*; D016032:Randomized Controlled Trials as Topic; D018582:Sick Leave / Q000706:statistics & numerical data*