Validation of the Iranian Version of the ECOS-16 Questionnaire in Patients with Osteoporotic Vertebral Fractures

Abstract

<sec><title>Study Design</title><p>Prospective clinical study.</p></sec><sec><title>Purpose</title><p>To translate and validate the Quality of Life Questionnaire of the European Foundation for Osteoporosis (ECOS-16) in patients with osteoporotic vertebral fractures in Iran.</p></sec><sec><title>Overview of Literature</title><p>It is important to assess the psychometric properties of instruments measuring patient-reported outcomes.</p></sec><sec><title>Methods</title><p>The translation was performed using the backward-forward translation method. The final version was generated by consensus among the translators. Every woman who had a T-score of &lt;−2.5 completed ECOS-16. Patients were divided into two study groups according to the World Health Organization's criteria: those with at least one vertebral fracture (surgery group) and those with no fractures (control group). They were asked to respond to the questionnaire at three points in time: preoperative and twice within 1-week interval after surgery assessments (6-month follow-up). The 36-item short-form health survey (SF-36) also was completed. The psychometric properties of the questionnaire were assessed using internal consistency, test-retest reliability, convergent validity, discriminant validity, and responsiveness.</p></sec><sec><title>Results</title><p>Of 137 recruited women, 39 underwent surgery and 98 did not. Analysis of the ECOS-16 scales showed an appropriate reliability with Cronbach's alpha of &gt;0.70 for all scales. Test-retest reliability as indicated by intraclass correlation coefficient was found to be 0.85 (0.68–0.91). Additionally, the correlation of each item with its hypothesized domain of the ECOS-16 showed acceptable results, suggesting that the items had a substantial relationship with their own domains. Further analysis also indicated that the questionnaire was responsive to change (effect size, 0.85; standardized response mean, 0.93) (<italic>p</italic>&lt;0.001). Significant correlations existed between scores of similar subscales of ECOS-16 and SF-36 (<italic>p</italic>&lt;0.001).</p></sec><sec><title>Conclusions</title><p>ECOS-16 is an acceptable, reliable, valid, and responsive measure to assess the quality of life in patients with osteoporotic vertebral fractures.</p></sec>