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Speaking fundamental frequency and individual variability in Caucasian and African American school-age children.

PURPOSE
The purpose of this study was to examine the speaking fundamental frequency (SFF) and pitch sigma (individual SFF variability) of African American and Caucasian children ages 6 through 8 years.


METHOD
Participants in this study included 63 Caucasian and African American children recruited from 6 urban schools and 1 day care center. All participants passed hearing and speech-language screenings. Spontaneous speech samples for SFF measurement were elicited from each child in a quiet room in the school he or she attended.


RESULTS
Results of this study found that there were no significant differences in SFF or pitch sigma as a function of the races or ages studied. It appeared that a single value for each variable could reasonably characterize African American and Caucasian children at ages 6, 7, or 8: 244.8 Hz for SFF (SD = 30.0 Hz) and 2.06 semitones (STs) for pitch sigma (SD = 0.82 ST).


CONCLUSIONS
This study is the most comprehensive to date on SFF and pitch sigma for African American and Caucasian children ages 6 to 8 years. Results supported previous observations that SFF is stable throughout the prepubescent years. Furthermore, findings also suggest that pitch sigma is stable across the ages of 6 to 8 years, regardless of race.