Cross-cultural adaptation and psychometric evaluation of the Yoruba version of Oswestry disability index

Abstract

IntroductionLow Back Pain is a common public health problem worsened by maladaptive beliefs and incongruent back pain behaviour. It is imperative to develop outcome measures to assess these beliefs among patients with chronic LBP. This study aimed to cross-culturally adapt and determine the psychometric properties of the Yoruba version of the ODI (ODI-Y).\n\nMethodsThe ODI-Y was cross-culturally adapted following the process involving forward translation, synthesis, backward translation, expert review, and pilot testing. One hundred and thirty-six patients with chronic LBP took part in the validation of the ODI-Y; 86 of these individuals took part in the test-retest reliability (within 1-week interval) of the translated instrument. Internal consistency and test-retest reliability of the ODI-Y were determined using the Cronbachs alpha and intra-class correlation. Other psychometric properties explored included the factor structure and fit, convergent validity, standard error of measurement and the minimal detectable change.\n\nResultsThe mean age of the respondents was 50.5{+/-}10.6years. The ODI-Y showed a high internal consistency, with a Cronbachs alpha () of 0.81. Test-retest of the Yoruba version of the ODI within 1-week interval yielded an Intra-Class Correlation coefficient of 0.89. The ODI-Y yielded a two-factor structure which accounted for 51.7% of the variance but showed poor fit. Convergent of ODI-Y with the visual analogue scale was moderate (r=0.30; p=0.00). The standard error of measurement and minimal detectable change of the ODI-Y were 2.0 and 5.5.\n\nConclusionsThe ODI was adapted into the Yoruba language and proved to have a good factor structure and psychometric properties that replicated the results of other obtainable versions. We recommend it for use among Yoruba speaking patients with low-back pain.