Psychometric Properties Study of the Oswestry Disability Index in a Spanish Population With Previous Lumbar Disc Surgery: Homogeneity and Validity

Study Design. Evaluation of the psychometric properties of a questionnaire. Objective. To assess the psychometric properties of the Spanish version of the Oswestry Disability Index (ODI) in a Spanish population with previous lumbar disc surgery. Summary of Background Data. ODI is frequently used for measuring disability in spinal disorders. In 1995, ODI was translated and transculturally adapted into the Spanish context; its content and apparent validity, internal consistency and test–retest reliability were demonstrated for a Spanish population with lumbar pain. However, this score has not been tested in terms of discriminative capacity (floor and ceiling effects) and construct validity. Methods. Two hundred seventy-five patients who had previously undergone surgical treatment for disc lumbar herniation completed the ODI, Short-Form 36 (SF36), EuroQol-5D (EQ5D), and Numerical Rating Scale for Back Pain. Internal consistency, floor and ceiling effects and construct validity (convergent, divergent, and “known-groups” validities) were assessed. Results. Spanish ODI showed a very good internal consistency: Cronbach-α coefficient for ODI score was 0.928; Cronbach-α coefficient, if the item was deleted, did not increase by more than 0.1 for each item; and Item-total correlations ranged from strong to very strong. There was floor effect for both ODI score and for all individual items. There was no ceiling effect. Spanish ODI showed very good construct validity...
Source: Spine - Category: Orthopaedics Tags: HEALTH SERVICES RESEARCH Source Type: research