title: Outcome determinants of subacute low back pain.
abstract: METHODS
  Descriptive prognostic study.
  
  
  OBJECTIVE
  To identify outcome determinants of subacute low back pain.
  
  
  BACKGROUND
  The factors predicting recovery from prolonged back pain among working adults are largely unknown.
  
  
  METHODS
  One hundred sixty-four employed patients with subacute (duration of pain 4-12 weeks) daily low back pain were recruited from primary health care to a randomized study. Data on potential predictive factors were collected before randomization. In multiple regressions using repeated measures analysis, the treatment received was adjusted when determining the impact of the predictive factors. Dependent outcome variables used were pain, perceived functional disability, generic health-related quality of life, satisfaction with care, days on sick leave, use of health care, and costs of health care consumption measured, at 3-, 6-, and 12-month follow-ups.
  
  
  RESULTS
  Age and intensity of pain at baseline predicted most of the outcomes. The perceived risk of not recovering was a stronger determinant of outcome than gender, education, or self-rated health status (which did not have any predictive value) or body mass index, expectations of treatment effect, satisfaction with work, or the presence of radicular symptoms below the knee (only slight predictive value). The only factors predicting the duration of sick leave were the duration of sick leave at baseline and the type of occupation.
  
  
  CONCLUSIONS
  Age and intensity of pain are the strongest predictors of outcome. Accumulation of days on sick leave is predicted by the duration of sick leave at entry and the type of work, but not by pain, perceived disability, or satisfaction with work.
authors.affiliation: Department of Occupational Medicine, Finnish Institute of Occupational Health, Helsinki, Finland. kaija.karjalainen@occuphealth.fi
authors.forename: Kaija
authors.initials: K
authors.lastname: Karjalainen
authors.forename: Antti
authors.initials: A
authors.lastname: Malmivaara
authors.forename: Pertti
authors.initials: P
authors.lastname: Mutanen
authors.forename: Timo
authors.initials: T
authors.lastname: Pohjolainen
authors.forename: Risto
authors.initials: R
authors.lastname: Roine
authors.forename: Heikki
authors.initials: H
authors.lastname: Hurri
mesh_terms: D000041:Absenteeism; D000208:Acute Disease; D000328:Adult; D005260:Female; D017048:Health Care Costs; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000191:economics / Q000628:therapy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017060:Patient Satisfaction; D011379:Prognosis; D011788:Quality of Life