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

ABSTRACT

STUDY DESIGN: Prospective clinical study. PURPOSE: 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. OVERVIEW OF LITERATURE It is important to assess the psychometric properties of instruments measuring patient-reported outcomes. METHODS: 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 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) (p<0.001). Significant correlations existed between scores of similar subscales of ECOS-16 and SF-36 (p<0.001). CONCLUSIONS: ECOS-16 is an acceptable, reliable, valid, and responsive measure to assess the quality of life in patients with osteoporotic vertebral fractures.