“…1,19,23,[26][27][28][29][30][31][32] The VRP is known to be sensitive to gender and age, consequently separate norms for male and female subjects and children are reasonable. 3,9,14,[22][23][24][25][30][31][32][33][34][35] Although the significant differences between prepubescent child and adult voices are well established, only limited data on normal vocal capabilities for trained voices in school-aged children is available. 8,[20][21][22] This may be because of some difficulties in the testing of children (more time consuming, less precise) and of variability of the data as a result of rapid and obvious changes in the anatomy and physiology of the vocal tract during development.…”