title: Determinants for improvement in different back pain measures and their influence on the duration of sickness absence.
abstract: METHODS
  Prospective cohort study.
  
  
  OBJECTIVE
  To identify the determinants for improvement in pain, functional limitations, and quality of life in low back pain (LBP) patients, and to evaluate whether return to work (RTW) can be predicted by these factors and associated improvement in health-related aspects.
  
  
  BACKGROUND
  It is unclear to what extent prognostic factors for the course of LBP and consequent functional limitations are similar to prognostic factors for RTW.
  
  
  METHODS
  A total of 103 LBP patients on sickness absence for 3 to 12 weeks filled out three questionnaires: at inclusion, and after 3 and 6 months. Information on the duration of sickness absence was gathered from occupational health services.
  
  
  RESULTS
  Different personal characteristics determined pain, functional limitations, and quality of life at baseline. These dimensions all improved over time, significantly during the first 3 months. Working at 3 months had a positive impact on all three dimensions. In the multivariate model, RTW was positively associated with male gender and recurrent LBP, whereas it was negatively associated with the level of functional limitations at baseline.
  
  
  CONCLUSIONS
  Except for male gender, the primary determinants for improvement in pain, functional limitations, and quality of life were not associated with RTW. Although there is a large coherence in the improvement in the outcome measures, RTW seems primarily determined by the level of experienced functional limitations.
authors.affiliation: The Netherlands Expert Centre for Work Related Musculoskeletal Disorders, Erasmus Medical Center, Rotterdam, The Netherlands. e.faber@erasmusmc.nl
authors.forename: Elske
authors.initials: E
authors.lastname: Faber
authors.forename: Alex
authors.initials: A
authors.lastname: Burdorf
authors.forename: Sita M A
authors.initials: SM
authors.lastname: Bierma-Zeinstra
authors.forename: Harald S
authors.initials: HS
authors.lastname: Miedema
authors.forename: Bart W
authors.initials: BW
authors.lastname: Koes
mesh_terms: D000041:Absenteeism; D000328:Adult; D000368:Aged; D001416:Back Pain / Q000503:physiopathology* / Q000628:therapy*; D015331:Cohort Studies; D006233:Persons with Disabilities; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000503:physiopathology; D011379:Prognosis; D011446:Prospective Studies; D011788:Quality of Life; D012008:Recurrence; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013997:Time Factors; D014937:Work