Objective: Laryngeal diadochokinetic (L-DDK) rate is a measure of laryngeal neural integrity. The objectives for this study included the following: (1) establish the first comprehensive pediatric normative database for L-DDK rates (DDK) using the Voice Evaluation Suite, a computerized voice analysis program; and (2) analyze normal L-DDK rates for age and gender differences.
Study design: Cross-sectional study with planned data collection.
Setting: Outpatient pediatric otolaryngology clinic.
Subjects and methods: Three hundred seven children aged 4 to 18 with normal voices. L-DDK rates were collected during a 6-month period. Main outcome measures included age, gender, and L-DDK rates.
Results: Three hundred seven children (151 girls and 156 boys) were evaluated. There was no statistically significant difference between the overall mean L-DDK rate of boys (2.69 syllables/s) compared to girls (2.55 syllables/s; P > .05). Further analysis of all individual age groups did not reveal any statistical significance between boys and girls. There was a statistically significant difference among children aged 4 to 11 compared to those 12 to 18 years old. Among boys aged 4 to 11, the mean rate was 2.49 syllables per second, whereas among 12- to 18-year-olds, the rate was 2.95 syllables per second (P < .01). The mean rate was 2.40 syllables per second among girls aged 4 to 11 and 2.74 syllables per second for those aged 12 to 18 (P < .01).
Conclusion: This is the largest normative pediatric L-DDK analysis in the English literature. The findings suggest that neurolaryngeal development approaches adult maturation at the beginning of the teenage years. These data have the potential application for objective measurement of neurolaryngeal coordination in children with neurologic impairment and also in children who have undergone nerve reinnervation procedures.
Keywords: DDK; diadochokinetic; pediatric speech; pediatric voice.