Supplementary Material for: Questionário de Saúde e Higiene Vocal (Vocal Health and Hygiene Questionnaire): Development, Validation, and Cutoff Value

Objective. To develop and validate an instrument for assessing knowledge of health and vocal hygiene.
Study Design. Cross-sectional nonrandomized prospective study.
Methods. A total of 41 voice specialists classified 365 vocal aspects as positive, negative, or having no influence. Additionally, 50 dysphonic and 50 non-dysphonic participants completed the initial version of the Vocal Health and Hygiene Questionnaire (QSHV). The QSHV was submitted to psychometric measures.
Results. Of the 365 items, 45 demonstrated interrater reliability greater than 0.950. Five items were excluded due to conceptual or semantic redundancy. The initial version of the QSHV comprised 40 items, of which 9 failed to distinguish between dysphonic and non-dysphonic participants and were subsequently removed. Dysphonic participants rated their own vocal quality as poorer, obtained lower QSHV scores, and reported higher vocal handicap. The instrument showed high internal consistency (Cronbach’s alpha = 0.881) and excellent test-retest reliability (p = 0.804). The mean QSHV score was 17.84 for dysphonic participants and 29.12 for non-dysphonic participants (p < 0.001). A cutoff score of 23 points on the QSHV achieved optimal sensitivity and specificity (100%).
Conclusions. The QSHV was proved to be a responsive and reliable protocol for evaluation of knowledge in health and vocal hygiene; The findings also indicate that individuals with dysphonia possess less knowledge about vocal health. The QSHV demonstrated strong diagnostic accuracy in distinguishing dysphonic from non-dysphonic individuals.
Keywords. Voice; Dysphonia; Vocal Hygiene; Knowledge; Surveys and Questionnaires; Validation Study; Speech-Language Pathology