The purpose of this study was to develop self-reported vocal abuse and misuse checklist for children with vocal nodules, and to evaluate its reliability and validity.
Newly developed items of vocal abuse and misuse behaviors were categorized according to four conditions : school condition, after-school condition, home condition, and dietary habit condition related to reflux.
Content validity was estimated by four certified speech-language pathologists who are specialized in voice and items to score more than 3-point were chosen to be checklist. Construct validity was also estimated by calculating correlation coefficient among items within each condition. Finally, 8- items in school condition, 4-items at after-school condition, 4-items at home condition, and 3-items in dietary habit condition were completed.
Twenty-six normal children and twenty-one children who diagnosed vocal nodules from from June 2016 to May 2017 were recruited in this study. For acoustic analysis, sustained /a/ vowel was recorded at comfortable pitch and loudness in noise treated room from normal and dysphonic children .
Children in our dysphonic and control group were asked to fill out the preliminary checklist. For the test re-test analysis we used a same group who filled out after 1 week. Internal consistency was analyzed through Cronbach''s α coefficient. The test-retest reliability was assessed by determining Pearson''s correlation coefficient. Independent t- test was used to compare the scores of the checklist as well as acoustic measures using MDVP of the control group with the dysphonic group.
The results showed that newlyed developed vocal abuse and misuse checklist provided a high internal consistency in school condition (α=0.781), after-school condition(α= .698), home condition(α=.607) and a moderate internal consistency in dietary habit condition(α=.510) and test-retest reliability of its subscales: school condition (S) 0.715, After-school condition (A) 0.702, home condition (H) 0.711, dietary habit condition (D) 0.552.
In addition, significant differences were found in scores of all conditions except in dietary habit condition between normal and dysphonic group. Finally, significant correlation were observed in jitter percent (r = .453), RAP(r = .462), and VTI(r = .481) between total scores and MDVP parameters.
Accordingly, newly developed checklist can be useful for measuring the vocal abuse and misuse behaviors affected to voice and feasible to apply the indirect voice therapy for children with vocal nodules.