F Mozzanica1, C Robotti2, D Ginocchio3, C Bulgheroni4, R Lorusso2, M Behlau5, A Schindler2, F Ottaviani4. 1. Department of Biochemical and Clinical Science "Luigi Sacco", University of Milan, Milan, Italy. Electronic address: francesco.mozzanica@gmail.com. 2. Department of Biochemical and Clinical Science "Luigi Sacco", University of Milan, Milan, Italy. 3. Audiology Unit, Department of Clinical Sciences and Community, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico,University of Milan, Milan, Italy. 4. Division of Otorhinolaryngology, San Giuseppe Hospital, IRCCS Multimedica, University of Milan, Milan, Italy. 5. Centro de Estudos da Voz-CEV, Sao Paulo, Brazil.
Abstract
OBJECTIVES: To evaluate the reliability and validity of the Italian Voice Symptom Scale (I-VoiSS). STUDY DESIGN: Cross-sectional, nonrandomized, prospective study with controls. METHODS: The study consisted of five phases: item generation, reliability analysis, normative data generation, validity and responsiveness analysis. A group of 113 dysphonic patients was enrolled for the internal consistency analysis. Seventy-three of them completed the I-VoiSS twice, 2 weeks apart, for test-retest reliability analysis. A group of 150 vocally healthy participants completed the I-VoiSS for normative data generation. I-VoiSS scores obtained by dysphonic and vocally healthy participants were compared for validity analysis. I-VoiSS scores were correlated with those of the Italian version of the Voice Handicap Index (I-VHI) in 49 dysphonic patients for criterion validity analysis. I-VoiSS scores obtained in a group of 37 nonsmoker dysphonic patients before and after surgical treatment for vocal fold polyps were compared for responsiveness analysis. Finally, the cutoff value of the I-VoiSS was calculated. RESULTS: All the enrolled participants managed to complete the I-VoiSS autonomously. Internal consistency and test-retest were satisfactory (α = 0.92 and r = 0.91). A significant difference in the I-VoiSS scores between the dysphonic and vocally healthy participants was found (p = 0.001). Positive significant correlations were found between I-VoiSS and I-VHI scores (r = 0.85). I-VoiSS scores obtained in the pretreatment condition were significantly higher than those obtained after surgery (p = 0.001). The cutoff value of I-VoiSS was 15.5. CONCLUSION: I-VoiSS is reliable, valid, responsive to changes, and recommended for clinical practice and outcome research.
OBJECTIVES: To evaluate the reliability and validity of the Italian Voice Symptom Scale (I-VoiSS). STUDY DESIGN: Cross-sectional, nonrandomized, prospective study with controls. METHODS: The study consisted of five phases: item generation, reliability analysis, normative data generation, validity and responsiveness analysis. A group of 113 dysphonic patients was enrolled for the internal consistency analysis. Seventy-three of them completed the I-VoiSS twice, 2 weeks apart, for test-retest reliability analysis. A group of 150 vocally healthy participants completed the I-VoiSS for normative data generation. I-VoiSS scores obtained by dysphonic and vocally healthy participants were compared for validity analysis. I-VoiSS scores were correlated with those of the Italian version of the Voice Handicap Index (I-VHI) in 49 dysphonicpatients for criterion validity analysis. I-VoiSS scores obtained in a group of 37 nonsmoker dysphonic patients before and after surgical treatment for vocal fold polyps were compared for responsiveness analysis. Finally, the cutoff value of the I-VoiSS was calculated. RESULTS: All the enrolled participants managed to complete the I-VoiSS autonomously. Internal consistency and test-retest were satisfactory (α = 0.92 and r = 0.91). A significant difference in the I-VoiSS scores between the dysphonic and vocally healthy participants was found (p = 0.001). Positive significant correlations were found between I-VoiSS and I-VHI scores (r = 0.85). I-VoiSS scores obtained in the pretreatment condition were significantly higher than those obtained after surgery (p = 0.001). The cutoff value of I-VoiSS was 15.5. CONCLUSION: I-VoiSS is reliable, valid, responsive to changes, and recommended for clinical practice and outcome research.