Reproducibility and clinical and concurrent validity of the MSF-4: a four-item male sexual function questionnaire for...

The MSF-4 (Male Sexual Function 4-item) questionnaire is a condition-specific four-item scale of men's sexuality. We describe two studies that were conducted to assess the reproducibility and validity of the MSF-4 questionnaire.

Study 1 was a Phase III, multicenter study with a double-blind, parallel group design which was conducted in five countries. The objectives were to check the construct validity and factorial structure of the MSF-4 along with internal consistency reliability and clinical validity. Study 2 was a longitudinal, noncomparative, observational multicenter study to assess the reproducibility and the clinical and concurrent validity of the MSF-4.

When exploratory factor analysis was performed with a free number of factors, the variability of the global MSF-4 score was based on a single factor across all countries in Study 1 except Spain. There was a high level of internal consistency reliability (Cronbach's alphas 0.68-0.90) and the MSF-4 was able to significantly discriminate different health states as assessed by the International Prostate Symptom Score (I-PSS) or Quality of Life (QoL) questionnaire. In study 2, there was a significant correlation between the MSF-4 and the International Index of Erectile Function (IIEF) scores (p = .0001 for all items) especially erectile function (correlation coefficient -0.77). The MSF-4 was able to distinguish among patients with differing degrees of benign prostatic hyperplasia (BPH) symptoms as measured by the I-PSS (p = .0001) and between those with and without sexual disorders (p = .0001).

The MSF-4 is a psychometrically validated questionnaire with good reproducibility and clinical validity, which allows easy and appropriate assessment of male sexual function in the clinical setting.