The Multiple Sclerosis Intimacy and Sexuality Questionnaire (MSISQ): Validation of the Turkish version in patient with multiple sclerosis

•Multiple Sclerosis Intimacy and Sexuality Questionnaire (MSISQ-15) was successfully translated, adapted, and validated into the Turkish language.•The MSISQ-15 is a comprehensive questionnaire to obtain information about the cause of sexual dysfunction in Turkish women with MS and to evaluate the level of sexual dysfunction.•By using MSISQ-15, rehabilitation professionals, neurologists and sex therapists can detect sexual dysfunction at an early stage and reduce the cost of sexuality treatment.•This tool also will allow the person with MS and their healthcare team to focus on the real problem (i.e., primary, secondary, or tertiary) causing the sexual dysfunction. This study aimed to psychometrically evaluate the Turkish version of the Multiple Sclerosis Intimacy and Sexuality Questionnaire (MSISQ-15) in women with MS. The study included 130 women with MS. The Turkish linguistic validation process of the original English MSISQ-15 was performed according to standardized guidelines. Reliability analysis was evaluated with test-retest analysis and intra-class correlation (ICC). Internal consistency between the items was analyzed using the Cronbach's alpha coefficient. Item analysis results were used to assess the contribution of the items to the scale. In evaluating the validity of the scale, the relationship between the MSISQ and the Female Sexual Function Index (FSFI), the Multiple Sclerosis Quality of Life Questionnaire-54 (MSQOL-54), and the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PSIQ-12) was investigated. Psychometric properties were analyzed using internal consistency, test-rest reliability, construct validity, and floor-ceiling effect. The internal consistency of the Turkish MSISQ-15 was strong in terms of both sub-dimension score and the total score (Cronbach's a coefficient > 0.80). The test-retest reliability of the scale was very strong (ICC > 0.90). A medium-high correlation was found between the MSISQ-15 and the MSQOL-54, the FSFI, and the PSIQ-12 (between r = -0.448 and r = -0.798, p