Validation of the Swedish version of the Female Sexual Function Index (FSFI) in women with hypoactive sexual desire disorder.

INTRODUCTION: The Female Sexual Function Index (FSFI) has been validated for use in many countries. It has been used for clinical and research purposes in Sweden, but the reliability and validity of the Swedish version have never been tested.

AIM: The aim of this study was to investigate the psychometric properties of the Swedish version of the FSFI.

METHODS: After informed consent, 50 women with a diagnosis of hypoactive sexual desire disorder (HSDD) and 58 age-matched healthy volunteers completed the questionnaires.

MAIN OUTCOME MEASURES: Reliability was tested by Cronbach's alpha and test-retest by Pearson's correlation, convergent validity by correlation of the FSFI and the Sexual Function Questionnaire (SFQ), divergent validity by correlation of FSFI and the Symptoms Checklist-90-Revised (SCL-90-R), and discriminant validity by Student's t-test and chi-square test to assess differences between women with and without HSDD.

RESULTS: Cronbach's alpha was 0.90-0.96 and test-retest reliability was good (r=0.86-0.93) for all domains in the whole sample; reliability was low for lubrication and pain in the control group. Correlations between all corresponding domains of the FSFI and the SFQ were high for the whole sample (r=0.74-0.87) and moderate to high for both the clinical and the control group. There was no correlation between most FSFI domains and the SCL-90-R. Discriminant validity was very good for each of the FSFI domains (P=0.001, t=7.05-15.58), although the controls reported relatively low scores on the desire domain. The total FSFI score was 31.37 (standard deviation [SD] 2.66) for the clinical group and 17.47 (SD 5.33) for the controls (P=0.001, t=15.99).

CONCLUSION: The Swedish version of the FSFI can be used as a validated and reliable instrument for assessing sexual function in women with HSDD.