HEALTH SERVICES RESEARCH SPINE Volume 38, Number 4, pp E237–E243 ©2013, Lippincott Williams & Wilkins Spine www.spinejournal.com E237 Validation and Cross-Cultural Adaptation of the Polish Version of the Oswestry Disability Index Grzegorz Miekisiak, MD,* Marta Kollataj, MSc,† Jan Dobrogowski, MD, PhD,† Wojciech Kloc, MD, PhD,‡ Witold Libionka, MD, PhD,‡ Mariusz Banach, MD,§ Dariusz Latka, MD, PhD,¶ Tomasz Sobolewski, MD,¶ Adam Sulewski, MD, PhD,  Andrzej Nowakowski, MD, PhD,  Grzegorz Kiwic, MD,** Adam Pala, MD,†† Tomasz Potaczek, MD,‡‡ and Maciej Gierlotka, MSc* Study Design. Validation of a translated, culturally adapted questionnaire. Objective. To translate and culturally adapt a Polish version of the Oswestry Disability Index (ODI) and to validate its use in Polish patients. Summary of Background Data. The ODI is among the most popular questionnaires used to evaluate back pain–related disability. To our knowledge no validated Polish version of the index was available at the time our study was initiated. Methods. The questionnaire was translated and culturally adapted by 2 independent translators and approved by expert committee. Final version was included in the booklet consisting in addition of a previously validated Roland–Morris disability questionnaire, VAS for low back and leg and 3 Likert scale questions (pain medications, pain frequency, disability). It was tested on 169 patients with chronic low back pain, 164 (97%) of them were enrolled, and 84 of 164 (53%) returned the completed retest booklet within 2 to 14 days after the baseline test. There were no differences between the 2 groups in demographic and clinical parameters. Test-retest reliability, internal consistency, and construct validity were investigated. Results. The mean ODI (standard deviation [SD]) was 48.45 (18.94); minimum 2, maximum 94. The Cronbach α for baseline questionnaires (n = 164) was 0.90. Concurrent validity, measured by comparing ODI responses with the results of the Roland–Morris L ow back pain (LBP) is one of the leading causes of mor- bidity in industrialized countries and accounts for an enormous psychosocial and socioeconomic burden. 1 –3 Despite its ubiquitous prevalence, little is known about the pathomechanism, and many commonly used treatment modalities are supported by limited evidence base. 4 ,5 There- fore, valid and reliable instruments measuring LBP-related disability are necessary for clinical evaluation and outcome monitoring. Because there are no consistent physiological measures to quantify the degree of physical impairment, the use of patient-reported questionnaires has become the most popular method of evaluation. LBP is a complex clinical problem that affects virtually all domains of life and for that reason, it is not sufficient to merely measure the intensity of pain with the use of simple tools such as visual analogue scale (VAS). During past decades, many surveys have been devel- oped to assess LBP and measure the treatment outcomes. 6 –11 Although there are no “gold standards” accepted in the field of spine-related research, 2 questionnaires are recom- mended in up-to-date reviews 7 ,12 : the Oswestry Disability Index (ODI) and the Roland–Morris disability questionnaire (RMDQ). The first version of the ODI 1.0 was published in 1980 by Fairbank et al . 13 It is comprised of 10 sections of single-choice questions addressing the pain intensity (first section) and the influence of pain on 9 domains of daily living: personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling. The total score is adjusted for missing answers and calibrated to be represented on a scale of 0 to 100 where From the *Department of Neurosurgery, Specialist Medical Center, Polanica- Zdroj, Poland; †Department of Pain Research and Treatment of Jagiellonian University, Krakow, Poland; ‡Department of Neurosurgery, Pomeranian Traumatology Center, Gdansk, Poland; §Department of Neurosurgery, Military Clinical Hospital, Bydgoszcz, Poland; ¶Department of Neurosurgery, Regional Medical Center, Opole, Poland; Department of Spinal Surgery, University of Medical Sciences, Poznan, Poland; **Department of Neurosurgery, Regional Specialist Hospital, Jastrzebie-Zdroj, Poland; ††Spine Department, District Orthopaedic Hospital, Piekary Slaskie, Poland; and ‡‡Department of Orthopaedics and Rehabilitation, Jagiellonian University, Zakopane, Poland. Acknowledgment date: June 6, 2012. First revision date: November 13, 2012. Acceptance date: November 16, 2012. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. No relevant financial activities outside the submitted work. Address correspondence and reprint requests to Grzegorz Miekisiak, MD, Oddzial Neurochirurgii, Specjalistyczne Centrum Medyczne, ul. Jana Pawla II 2 57-320, Polanica-Zdroj, Poland; E-mail: gmiekisiak@gmail.com disability questionnaire score was very good (r = 0.607, P < 0.001). The correlation with VAS back was fair (r = 0.37, P < 0.001) and with VAS leg was good (r = 0.56, P < 0.001). The tested ODI had excellent test-retest reliability, the intraclass correlation coefficient was 0.97 and standard error of measurements was 3.54, the resulting minimal detectable changes at the 95% confidence level was 10. Conclusion. The results of this study indicate that the Polish version of the ODI is a reliable and valid instrument for the measurement of disability in Polish-speaking patients with lower back pain. Key words: outcome, Oswestry, validation. Spine 2013;38: E237–E243 DOI: 10.1097/BRS.0b013e31827e948b Copyright © 2013 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.