title: A consensus approach toward the standardization of back pain definitions for use in prevalence studies.
abstract: METHODS
  A modified Delphi study conducted with 28 experts in back pain research from 12 countries.
  
  
  OBJECTIVE
  To identify standardized definitions of low back pain that could be consistently used by investigators in prevalence studies to provide comparable data.
  
  
  BACKGROUND
  Differences in the definition of back pain prevalence in population studies lead to heterogeneity in study findings, and limitations or impossibilities in comparing or summarizing prevalence figures from different studies.
  
  
  METHODS
  Back pain definitions were identified from 51 articles reporting population-based prevalence studies, and dissected into 77 items documenting 7 elements. These items were submitted to a panel of experts for rating and reduction, in 3 rounds (participation: 76%). Preliminary results were presented and discussed during the Amsterdam Forum VIII for Primary Care Research on Low Back Pain, compared with scientific evidence and confirmed and fine-tuned by the panel in a fourth round and the preparation of the current article.
  
  
  RESULTS
  Two definitions were agreed on a minimal definition (with 1 question covering site of low back pain, symptoms observed, and time frame of the measure, and a second question on severity of low back pain) and an optimal definition that is made from the minimal definition and add-ons (covering frequency and duration of symptoms, an additional measure of severity, sciatica, and exclusions) that can be adapted to different needs.
  
  
  CONCLUSIONS
  These definitions provide standards that may improve future comparisons of low back pain prevalence figures by person, place and time characteristics, and offer opportunities for statistical summaries.
authors.affiliation: Population Health Research Unit, (URESP) Research Centre of the Laval University Affiliated Hospital, Québec, QC, Canada. clermont.dionne@uresp.ulaval.ca
authors.forename: Clermont E
authors.initials: CE
authors.lastname: Dionne
authors.forename: Kate M
authors.initials: KM
authors.lastname: Dunn
authors.forename: Peter R
authors.initials: PR
authors.lastname: Croft
authors.forename: Alf L
authors.initials: AL
authors.lastname: Nachemson
authors.forename: Rachelle
authors.initials: R
authors.lastname: Buchbinder
authors.forename: Bruce F
authors.initials: BF
authors.lastname: Walker
authors.forename: Mary
authors.initials: M
authors.lastname: Wyatt
authors.forename: J David
authors.initials: JD
authors.lastname: Cassidy
authors.forename: Michel
authors.initials: M
authors.lastname: Rossignol
authors.forename: Charlotte
authors.initials: C
authors.lastname: Leboeuf-Yde
authors.forename: Jan
authors.initials: J
authors.lastname: Hartvigsen
authors.forename: Päivi
authors.initials: P
authors.lastname: Leino-Arjas
authors.forename: Ute
authors.initials: U
authors.lastname: Latza
authors.forename: Shmuel
authors.initials: S
authors.lastname: Reis
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Gil Del Real
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Kovacs
authors.forename: Birgitta
authors.initials: B
authors.lastname: Oberg
authors.forename: Christine
authors.initials: C
authors.lastname: Cedraschi
authors.forename: Lex M
authors.initials: LM
authors.lastname: Bouter
authors.forename: Bart W
authors.initials: BW
authors.lastname: Koes
authors.forename: H Susan J
authors.initials: HS
authors.lastname: Picavet
authors.forename: Maurits W
authors.initials: MW
authors.lastname: van Tulder
authors.forename: Kim
authors.initials: K
authors.lastname: Burton
authors.forename: Nadine E
authors.initials: NE
authors.lastname: Foster
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Macfarlane
authors.forename: Elaine
authors.initials: E
authors.lastname: Thomas
authors.forename: Martin
authors.initials: M
authors.lastname: Underwood
authors.forename: Gordon
authors.initials: G
authors.lastname: Waddell
authors.forename: Paul
authors.initials: P
authors.lastname: Shekelle
authors.forename: Ernest
authors.initials: E
authors.lastname: Volinn
authors.forename: Michael
authors.initials: M
authors.lastname: Von Korff
mesh_terms: D000203:Activities of Daily Living; D003697:Delphi Technique; D004185:Disability Evaluation; D005104:Expert Testimony; D006801:Humans; D007391:International Cooperation; D017116:Low Back Pain / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology; D012720:Severity of Illness Index; D009626:Terminology as Topic