title: The Oswestry Disability Index, the Roland-Morris Disability Questionnaire, and the Quebec Back Pain Disability Scale: translation and validation studies of the Iranian versions.
abstract: METHODS
  Cross-cultural translation and psychometric testing were performed.
  
  
  OBJECTIVE
  To cross-culturally translate the Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RDQ), and Quebec Back Pain Disability Scale (QDS) into Persian, and then investigate the psychometric properties of the Persian versions produced.
  
  
  BACKGROUND
  To the authors' knowledge, there is no validated instrument to measure functional status in Persian-speaking patients with low back pain (LBP) in Iran. To our knowledge, the widely used back-specific measures, the ODI, RDQ, and QDS, have not been translated and validated for Persian-speaking patients with LBP.
  
  
  METHODS
  The translation and cross-cultural adaptation of the original questionnaires were performed in accordance with published guidelines. A total of 100 patients with chronic LBP were asked to complete a questionnaire booklet (the Persian versions of the ODI, RDQ, QDS, Short Form Health Survey (SF-36), and visual analog scale measure of pain). There were 31 randomly select patients with chronic LBP asked to complete the second questionnaire booklet 24 hours later.
  
  
  RESULTS
  The Cronbach-alpha for the ODI, RDQ, and QDS was 0.75, 0.83, and 0.92, respectively. The ODI, RDQ, and QDS showed excellent test-retest reliability (intraclass correlation coefficient = 0.91, 0.86, and 0.86, respectively) (P < 0.01). The correlation among the ODI, RDQ, QDS and physical functioning scales of the SF-36 was -0.66, -0.62, and -0.69, respectively (P < 0.001). The correlation among the ODI, RDQ, and QDS and visual analog scale was 0.54, 0.36, and 0.46, respectively (P < 0.001).
  
  
  CONCLUSIONS
  The Persian versions of the ODI, RDQ, and QDS are reliable and valid instruments to measure functional status in Persian-speaking patients with LBP. They are simple and fast scales, and the use of them can be recommended in a clinical setting and future outcome studies in Iran.
authors.affiliation: Department of Physical Therapy, Faculty of Rehabilitation Sciences, Tehran University of Medical Sciences, Pich-e-Shemiran, Tehran, Iran. jmousavi@razi.tums.ac.ir
authors.forename: Sayed Javad
authors.initials: SJ
authors.lastname: Mousavi
authors.forename: Mohamad
authors.initials: M
authors.lastname: Parnianpour
authors.forename: Hossein
authors.initials: H
authors.lastname: Mehdian
authors.forename: Ali
authors.initials: A
authors.lastname: Montazeri
authors.forename: Bahram
authors.initials: B
authors.lastname: Mobini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003466:Cultural Characteristics; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D007492:Iran; D007802:Language; D017116:Low Back Pain / Q000503:physiopathology* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*