Validation of the Sexual Inhibition and Sexual Excitation Scales (SIS/SES) in Portugal: Assessing Gender Differences and Predictors of Sexual Functioning.

The Sexual Inhibition and Sexual Excitation Scales (SIS/SES) were developed to assess individual propensities for sexual excitation and sexual inhibition in men and women. The objective of the present study was to validate the Portuguese version of the SIS/SES and to investigate the degree to which SIS/SES scores predict different dimensions of Portuguese men's and women's sexual functioning. Gender differences were also examined. A community sample of 370 Portuguese men and 373 women completed self-report measures of sexual function (IIEF, Rosen et al., 1997; FSFI, Rosen et al., 2000) and of the propensity for sexual inhibition and sexual excitation (SIS/SES, Janssen et al., 2002a). Exploratory factor analysis revealed a three-factor solution further supported by confirmatory factor analysis. The three factors identified resemble the original ones, and reliability analyses indicated they have both satisfactory internal consistency and stability over time. Age and Sexual Inhibition Due to the Threat of Performance Failure (SIS1) were both significant negative predictors of men's sexual desire, erectile function, and orgasm. Sexual Excitation (SES) was a positive predictor of sexual desire in both men and women and of men's erectile function and of women's lubrication and orgasm. Age was also a significant and negative predictor of women's sexual desire. Significant gender differences were found for all three SIS/SES scales with men having significantly higher excitation and lower inhibition scores as compared to women. The Portuguese version of the SIS/SES was shown to be suitable for use within the Portuguese population in both clinical and basic research. Our findings provide further cross-cultural validation of the Dual Control Model of Sexual Response and underscore the importance of the role of excitatory and inhibitory processes in women's and men's sexual functioning and response.