Influence of Syllable Train Length and Performance End Effects on Estimation of Phonation Threshold Pressure

Objectives The purpose of this study was to determine whether the number of syllables collected and performance end effects had a significant effect on phonation threshold pressure (PTP) estimates. Methods Ten adult females with normal voices produced five- and seven-syllable trains of /pi/ at low, modal, and high pitches. The results were analyzed using repeated-measures analysis of variance to determine whether a difference existed in PTP when a five-syllable train was collected versus when a seven-syllable train was collected and whether the typically discarded first and last syllables within a train differed from the middle syllables. Results The results indicated that there was no significant difference in estimated PTP values when calculated from a five-syllable versus a seven-syllable train or between the first, middle, and last syllables within a train. Conclusions Based on these findings, it appears that a five-syllable train provides adequate information from which to estimate PTP values. Furthermore, these findings also suggest that within the five-syllable train, any three adjacent syllables could be used to estimate PTP. These findings are significant in developing a clinically standardized, effective, and efficient method for collecting PTP.