Fibromyalgia (FM) is the most common chronic pain syndrome encountered in medical practice, affecting females more than males, and the estimated prevalence of FM in Egypt is 1.3 %. The aim was to translate and adapt the Fibromyalgia Impact Questionnaire (FIQ) into Arabic and assess reliability and validity. The Arabic version of Fibromyalgia Impact Questionnaire (FIQ-A) was adapted following the forward/backward translation approach. Fifty-one female patients with FM were studied to assess psychometric properties of the FIQ-A. Reliability was analyzed by the correlation coefficient between test and retest. Internal consistency was checked by the Cronbach's alpha coefficient. Construct validity was assessed comparing FIQ-A with Health Assessment Questionnaire (HAQ), Health Assessment Questionnaire of Fibromyalgia (FHAQ), The Medical Outcome Survey Short-Form-36 (SF-36), and the Total Visual Analog Scale (TVAS) for FM symptom, and feasibility was assessed by the time taken in completing the FIQ-A and the proportion of patients completed the questionnaire. Patients studied were 33.2 ± 9.8 years old. Translation was concordant. Adaptation affected 4 sub-items of physical function. Test-retest correlation coefficient was 0.89 for total FIQ-A and Cronbach's alpha was 0.76. Excellent to good statistically significant correlations (p < 0.05) were found between the FIQ-A items and HAQ, FHAQ, and SF-36. The FIQ-A is a reliable, valid for measuring health status and physical function in Arabic-speaking FM patients.

El-Naby, M. A., et al. (2013). "Validation of an adapted arabic version of fibromyalgia syndrome impact questionnaire." Rheumatol Int 33(10): 2561-2567.

https://www.ncbi.nlm.nih.gov/pubmed/23681020