Normative vocal acoustic parameters for preschool and elementary school Egyptian children

Background: A reliable acoustic analysis necessitates the availability of standard normative values at different ages. Normative values of vocal acoustic parameters are readily available for the adult population but not much data are available for the pediatric population.

Objectives: Providing a database for the normative vocal acoustic parameters in preschool and elementary school Egyptian children to lay out an objective model for the diagnosis and optimal treatment of childhood voice disorders.

Methods: A total of 237 Egyptian children between the ages of 4 and 9 years from both genders were enrolled in the study. A Computer-assisted acoustic vocal analysis was done for all children.

Results: Fundamental frequency values differed significantly according to gender with higher measures in girls. Mean values of the fundamental frequency were 258.57 Hz ± 39.69, jitter percentage 0.85% ± 0.67, shimmer percentage 1.59% ± 1.03, fundamental tremors 1.64HZ ± 0.421, maximum phonation time 4.81sec. ± 1.73 and harmonic/noise ratio were 15.34 dB ± 10.65. A decline of measures of the fundamental frequency and jitter percentage with increasing age and an increase of values of harmonic/noise ratio and shimmer percentage in children residing in rural areas are observed.

Conclusion: This study provides an insight into the normative values of vocal acoustic parameters in preschool and elementary school Egyptian children. Comparable to other studies, both fundamental frequency and jitter percentage values show a decline with increasing age. Also, fundamental frequency values differ significantly among genders. The difference in socioeconomic environment seems to influence some of the vocal acoustic parameters in children.