Introduction. Although erectile dysfunction (ED) is known to hamper quality of life (QoL) of afflicted men and their partners, there are few validated instruments for assessing the couple's sexual QoL. The Sexual Life Quality of Life Questionnaire (SLQQ) was developed in the United States for this purpose, and so it has been used in clinical studies. Yet, the original description did not address some important psychometric properties included in the Food and Drug Administration 2006 guidance for patient-reported outcome instruments.
Aims. The aims of this study were to validate a Spanish language version of the modified SLQQ (mSLQQ), and to evaluate on it those psychometric properties lacking in the seminal description, namely discriminant validity and test–retest stability.
Methods. Psychometric validation of the translated SLQQ was conducted on 164 ED patients and their sexual partners, and 60 age-matched non-dysfunctional couples. At baseline, all subjects completed the mSLQQ QoL and the 12-item Short-Form Health Survey questionnaires, and the men the International Index of Erectile Function. Two weeks later, ED patients abstaining from any ED medication and their partners repeated the mSLQQ QoL (104 valid couples). Oral medication for ED was then prescribed. Four weeks thereafter, they completed the QoL and treatment satisfaction scales of the SLQQ.
Main Outcome Measures. The mSLQQ QoL scores of men and women at different times for psychometric analyses.
Results. Cronbach α coefficients indicated good internal consistency. Large differences between control and ED couples, and close association with ED severity demonstrated discriminant and convergent validity, respectively. High intra-class correlation coefficients and similar mean scores at first and second visits substantiated test–retest stability. Significant increases after treatment with robust effect size demonstrated sensitivity to change in both patients and partners.
Conclusions. This adaptation of the SLQQ shows psychometric properties comparable to the original description. The additional properties demonstrated here fully validate the mSLQQ as a tool for evaluating sexual QoL in ED patients and their partners. Gutiérrez P, Hernández P, Sanz E, Cardeñosa O, and Mas M. Further psychometric validation of the sexual life quality questionnaire for men with erectile dysfunction and their partners on a modified Spanish language version. J Sex Med 2009;6:2698–2706.