The Female Sexual Function Index: translation and validation of an Iranian version

Abstract

Introduction: Female sexual dysfunction (FSD) is a prevalent problem in the female population in Iran. A subjective assessment instrument that allows cross-cultural comparison of FSD is urgently needed.

Aim: The aims of the study were to translate, validate, and enhance cross-cultural comparability of an Iranian version (IV) of the Female Sexual Function Index (FSFI)-the IV-FSFI.

Methods: A total of 448 women (19-54 years, mean 29.7, standard deviation 7.3) from five different Iranian outpatient obstetrics and gynecology clinics were eligible for this study. The IV-FSFI was developed through forward and backward translation, revision by a research team, and a subsequent pilot study. After an interview for clinical diagnosis of FSD based on the Diagnostic and Statistical Manual of Mental Disorders, all participants completed the IV-FSFI for the validation study. Three hundred sixty-two women completed the IV-FSFI again, 4 weeks after the first visit.

Main outcome measures: Test-retest reliability was determined by Pearson's product-moment correlations. Reliability was tested using Cronbach's alpha coefficient. Construct validity was evaluated by principal component analysis using varimax rotation and by subsequent confirmatory factor analysis (CFA). Discriminant validity was assessed with between-groups analysis of variance.

Results: The overall test-retest reliability coefficients were high for each domain of the IV-FSFI (r ranging from 0.73 to 0.86) and the internal consistencies within the acceptable range (α from 0.72 to 0.90). Principal component analysis with varimax rotation revealed a best fitting five-factor structure similar to the original FSFI (χ(2) = 2.1, degree of freedom = 17, P < 0.001). CFA confirmed the underlying domain structure, supporting the factorial validity of the IV-FSFI.

Conclusions: In conclusion, the newly developed IV-FSFI has demonstrated to be a reliable and valid instrument with good psychometric properties that allows a quick and accurate preliminary screening of women with unknown sexual health status in clinics and other medical settings.