title: Translation of oswestry disability index into Tamil with cross cultural adaptation and evaluation of reliability and validity(§).
abstract: METHODS
  Prospective longitudinal validation study.
  
  
  OBJECTIVE
  To translate and cross-culturally adapt the Oswestry Disability Index (ODI) to the Tamil language (ODI-T), and to evaluate its reliability and construct validity.
  
  
  BACKGROUND
  ODI is widely used as a disease specific questionnaire in back pain patients to evaluate pain and disability. A thorough literature search revealed that the Tamil version of the ODI has not been previously published.
  
  
  METHODS
  The ODI was translated and cross-culturally adapted to the Tamil language according to established guidelines. 30 subjects (16 women and 14 men) with a mean age of 42.7 years (S.D. 13.6; Range 22 - 69) with low back pain were recruited to assess the psychometric properties of the ODI-T Questionnaire. Patients completed the ODI-T, Roland-Morris disability questionnaire (RMDQ), VAS-pain and VAS-disability at baseline and 24-72 hours from the baseline visit.
  
  
  RESULTS
  The ODI-T displayed a high degree of internal consistency, with a Cronbach's alpha of 0.92. The test-retest reliability was high (n=30) with an ICC of 0.92 (95% CI, 0.84 to 0.96) and a mean re-test difference of 2.6 points lower on re-test. The ODI-T scores exhibited a strong correlation with the RMDQ scores (r = 0.82) p<0.01, VAS-P (r = 0.78) p<0.01 and VAS-D (r = 0.81) p<0.01. Moderate to low correlations were observed between the ODI-T and lumbar ROM (r = -0.27 to -0.53). All the hypotheses that were constructed apriori were supported.
  
  
  CONCLUSIONS
  The Tamil version of the ODI Questionnaire is a valid and reliable tool that can be used to measure subjective outcomes of pain and disability in Tamil speaking patients with low back pain.
authors.affiliation: University of Western Ontario, Faculty of Health Sciences, Department of Health and Rehabilitation Sciences, London, Ontario, Canada and Clinical Outcomes Research Laboratory, Roth and McFarlane Hand and Upper Limb Center, St Joseph's Health care London, London, Ontario, Canada.
authors.forename: Joshua Israel
authors.initials: JI
authors.lastname: Vincent
authors.affiliation: McMaster University, School of Rehabilitation Science, Hamilton, Ontario, Canada and Co-Director of Clinical Outcomes Research Laboratory, Roth and McFarlane Hand and Upper Limb Center, St Joseph's Health care London, London, Ontario, Canada.
authors.forename: Joy Christine
authors.initials: JC
authors.lastname: Macdermid
authors.affiliation: University of Western Ontario, Department of Surgery, London, Ontario, Canada and Co-Director of Clinical Outcomes Research Laboratory, Roth and McFarlane Hand and Upper Limb Center, St Joseph's Health care London, London, Ontario, Canada.
authors.forename: Ruby
authors.initials: R
authors.lastname: Grewal
authors.affiliation: The Physiotherapy Center, Chennai, India.
authors.forename: Vincent Prabhakaran
authors.initials: VP
authors.lastname: Sekar
authors.affiliation: The Physiotherapy Center, Chennai, India.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Balachandran
keywords: Bland and Altman plot; Oswestry disability index-Tamil; Roland-Morris disability questionnaire; VAS.; construct validity; internal consistency; low back pain; reliability