Investigating the cepstral acoustic characteristics of voice in healthy children.

Objectives: This study aimed to determine the cepstral acoustic parameters that vary depending on age and gender in vocally healthy children, and to establish normative data for cepstral analysis.

Background: Cepstral measurements are among the strongest predictors of auditory-perceptual evaluation of voice and differentiate between healthy and dysphonic voices. More spesificially, ceptral peak prominence is accepted to be as a strong acoustic predictor of breathiness and overall severity of dysphonia. Cepstral measures determine voice quality reliably not only in sustained vowel samples but also in running speech samples. Determining the parameters related to the acoustic profile of children with normal voices can lead us to a better understanding of the effect of changes in the larynx and vocal fold structure during growth and development. There is a limited number of norm studies examining the cepstral acoustic properties of pediatric voice. Determining norm-specific values and clinical guidelines of cepstral acoustics according to the age and gender in vocally healthy children are utmost important.

Methods: A total of 160 vocally healthy children were divided into the following four age groups: Group-I included children within the age range of 4-7 years, Group-II included 7-11 years, Group-III 11-14 years, and Group-IV included children within the age range of 14-18 years. An equal number of male and female participants were assigned to each group. PENTAX Medical CSL Model 4500 was used for recording all tasks. For acoustic analysis, Multi-Dimensional Voice Program and Analysis of Dysphonia in Speech and Voice were used.

Results: Cepstral Peak Prominence (CPP), Cepstral Peak Prominence Standard Deviation (CPP SD), and Low-To-High Spectral Ratio (L/H Ratio) increased with age. It is found that the CPP parameter of all-voiced sentences and nasal-weighted sentences increased with age in boys, while no significant pattern was observed in any sample for girls. For L/H ratio, it can be said that there is a general increase with age in all speech samples, except for the vowel-weighted and voiceless plosive sentence samples, evident especially in the group above the age of 15 years. This study concluded that the CPP SD parameter in the vowel-weighted sentences increased with age in boys. It was also noticed in this study that CPP F0 standard deviation (SD) intervals were narrower in vowel-weighted, easy onset, and voiceless plosive sentence samples than in all-voiced, hard glottal attack and nasal-weighted sentence samples.

Conclusion: This study established cepstral acoustic normative values for a wide age range of the pediatric population. It is thought that age and gender specific cepstral acoustic findings presented in this study contributed to the related literature. In addition, to our knowledge, this is the first study that provides a normative cepstral acoustic database of the CAPE-V/Turkish sentences in the pediatric population.