Fabiana Zambon1, Felipe Moreti2, Vanessa Veis Ribeiro3, Chayadevie Nanjundeswaran4, Mara Behlau2. 1. Speech-Language Pathology Department, Universidade Federal de São Paulo - UNIFESP, São Paulo, São Paulo, Brazil; Centro de Estudos da Voz, São Paulo, São Paulo, Brazil; Sindicato dos Professores de São Paulo, São Paulo, São Paulo, Brazil. Electronic address: fabiana@sinprosp.org.br. 2. Speech-Language Pathology Department, Universidade Federal de São Paulo - UNIFESP, São Paulo, São Paulo, Brazil; Centro de Estudos da Voz, São Paulo, São Paulo, Brazil. 3. Speech-Language Pathology Department, Universidade Federal de São Paulo - UNIFESP, São Paulo, São Paulo, Brazil; Centro de Estudos da Voz, São Paulo, São Paulo, Brazil; Speech-Language Pathology Department, Universidade Federal de Sergipe - UFS, Lagarto, Sergipe, Brazil. 4. Department of Audiology and Speech-Language Pathology, East Tennessee State University, Johnson City, Tennessee.
Abstract
OBJECTIVES: To complete the validation and to study the psychometric properties of the Brazilian Portuguese version of the Vocal Fatigue Index (IFV). MATERIAL AND METHODS: This is a validation study of a diagnostic instrument utilizing a cross-sectional design and phases with quasi-experimental design. The total sample was composed of 212 participants, divided into two groups: Dysphonic Group and Vocally Healthy Group. All participants answered the VFI protocol. Data analysis consisted of the following steps: exploratory factor analysis, validity analysis, reliability analysis, sensitivity analysis, receiver operating characteristic, and area under the curve analysis. RESULTS: The Brazilian Portuguese version of the VFI called Índice de Fadiga Vocal-IFV, has 17 items and four factors. The IFV is a valid, reliable and sensible instrument to measure the self-perception of vocal fatigue. The threshold values for each factor was: 4.50 for tiredness and voice impairment; 3.50 for avoidance of voice use; 1.50 for physical discomfort and 8.50 for improvement of voice symptoms with rest. The threshold value for the total score was 11.50. CONCLUSION: The Brazilian Portuguese version of the VFI is a valid instrument to assess the self-perception of vocal fatigue, especially in dysphonic individuals.
OBJECTIVES: To complete the validation and to study the psychometric properties of the Brazilian Portuguese version of the Vocal Fatigue Index (IFV). MATERIAL AND METHODS: This is a validation study of a diagnostic instrument utilizing a cross-sectional design and phases with quasi-experimental design. The total sample was composed of 212 participants, divided into two groups: Dysphonic Group and Vocally Healthy Group. All participants answered the VFI protocol. Data analysis consisted of the following steps: exploratory factor analysis, validity analysis, reliability analysis, sensitivity analysis, receiver operating characteristic, and area under the curve analysis. RESULTS: The Brazilian Portuguese version of the VFI called Índice de Fadiga Vocal-IFV, has 17 items and four factors. The IFV is a valid, reliable and sensible instrument to measure the self-perception of vocal fatigue. The threshold values for each factor was: 4.50 for tiredness and voice impairment; 3.50 for avoidance of voice use; 1.50 for physical discomfort and 8.50 for improvement of voice symptoms with rest. The threshold value for the total score was 11.50. CONCLUSION: The Brazilian Portuguese version of the VFI is a valid instrument to assess the self-perception of vocal fatigue, especially in dysphonic individuals.