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Abstract:

The aim of the present investigation was to explore the occurrence of and factors related to hoarseness in ten- year-old children. In order to establish the prevalence of hoarseness in a group of normal children, a method to distinguish atypical from normal voices was introduced and the perceptual characteristics of hoarseness were identified.

Two hundred and sixty-eight ten-year-old children, 129 girls and 139 boys, from different parts of Sweden took part in the investigation. Their voices were perceptually evaluated along visual analog scales by a panel of seven speech-language pathologists, all experts on voice disorders.

Rank ordered rating means of the voices of 58 children, 24 girls and 34 boys, along 15 voice parameters, showed a discontinuity in the distribution for all parameters except pitch, breathiness and vocal fry. The discontinuities were used as borderlines between normal and deviant voice quality. A stepwise multiple regression analysis revealed that hyperfunction, breathiness and roughness are good predictors of hoarseness. The same predictors were identified in an investigation of the perceptual characteristics of connected speech and the sustained vowel [a:] of 50 children. In connected speech, hyperfunction was the most prominent variable for the perception of hoarseness, whereas for sustained vowels, roughness was the most salient voice characteristic. In a group of 205 children, 104 girls and 101 boys, 14% were identified as being hoarse, 11 girls and 17 boys. Chronic hoarseness was found in 6%. For children from densely populated areas, the prevalence was 21%.

Pitch and intensity ranges of 60 children were recorded and plotted in phonetograms. Vocal fold status was determined via videomicrolaryngo(strobo)scopy. Twelve percent of the children, all boys, had vocal nodules and 44% incomplete glottal closure. In general, the children had somewhat compressed phonetogram contours compared to adults, reflecting restricted dynamic vocal capabilities.

To identify factors related to hoarseness the parents were asked to answer questionnaires concerning elements of potential relevance to voice function and the teachers and the parents were asked to characterize the children in terms of personality traits as defined by adjective pairs. One study included 55 children, 22 girls and 33 boys, and the other 222 children, 111 girls and 111 boys. Gender, physical environment, temperament, hours spent per day in large groups and vocal strain were factors of significant relation to chronic hoarseness. Factors of importance to the occurrence of acute hoarseness were gender and vocal strain. Neither allergies, infections or other medical factors showed any significant relationship to hoarseness.

Conclusions: It was concluded that hoarseness in ten-year-old children is characterized by hyperfunction, breathiness and roughness. Physiological conditions in combination with socio-emotional factors make children vulnerable to vocal strain and predisposed to developing a hoarse voice. A breathy voice and/or an incomplete glottal closure may be regarded as normal in 10-year old children.

Keywords: Child voice, hoarseness, perceptual analysis, voice quality, visual analog scales, connected speech, sustained vowels, prevalence, acute hoarseness, chronic hoarseness, videolaryngoscopy, stroboscopy, incomplete glottal closure, vocal nodules, voice