The Validation of the Female Sexual Function Index, Male Sexual Function Index, and Profile of Female Sexual Function for Use in Healthy Young Adults.

Past research has typically used clinical samples to evaluate the validity of sexual function measures. As normal variations in sexually healthy individuals are of important research and clinical interest, evaluating the applicability of common sexual function measures to these populations is important. Factor structures of the Female Sexual Function Index (FSFI), Male Sexual Function Index (MSFI) (adapted for this investigation), and Profile of Female Sexual Function (PFSF) were examined in young, healthy men and women. We predicted the factor structures to be consistent with past evaluations. In a cross-sectional study, 1,258 participants (M age = 19.56 years; 59 % women) completed these measures. Confirmatory factor analyses did not initially support the factor structures. However, factor loadings showed marked differences between positively and negatively worded items. As such, each measure's factor structure was tested using multi-trait multi-method confirmatory factor analysis which accounted for variance due to item valence. These models supported the predicted structures of the FSFI and MSFI, whereas the PFSF's Responsiveness scale required modification, resulting in an Avoidance scale for both genders. This study was one of few to validate the FSFI in young, healthy adults and the first to examine the MSFI and PFSF in these populations. Additionally, this investigation was the first to propose a reconceptualization of the PFSF Responsiveness scale into an Avoidance scale. Lastly, our study highlights the significant impact of item valence on how individuals respond to questions regarding their sexual functioning.