The Sexual Function Evaluation Questionnaire (SFEQ) to evaluate effectiveness of treatment for sexual difficulties: development and validation in a clinical sample

Progress toward establishing the effectiveness of biopsychosocial treatment for patients with sexual problems is limited by the lack of brief measurement tools assessing change across various domains of the treatment model. We developed and psychometrically validated a new clinical evaluation tool, the Sexual Function Evaluation Questionnaire (SFEQ) to meet this gap. The SFEQ combines into a single scale the best performing items from two instruments that were piloted in a UK sexual problems clinic (n = 486): the Natsal-SF Clinical Version and the National Sexual Outcomes Group 1 measure. Internal construct validity evidence from exploratory and confirmatory factor analyses supported a 16-item measure consisting of one overarching dimension of overall sexual function distributed along four subscales: problem distress, partner relationship, sex life, and sexual confidence. The measure had satisfactory configural, metric, and scalar invariance over time and across groups based on gender, ethnicity, and age. Correlations with patient depression and anxiety demonstrated external validity. Change in scores over the course of therapy varied as predicted, with greater improvement in younger patients and in areas more amenable to change via therapy (sexual confidence and problem distress). The SFEQ is a brief clinical tool with the potential to assess sexual function and evaluate the effectiveness of biopsychosocial treatment programs.