[Show abstract][Hide abstract] ABSTRACT: To describe the origins of the task elicitation procedure for determining phonation threshold pressure and, through a literature review and online survey, describe published procedural, environmental, and participant variable departures from the original methodology.
Literature search terms included phonation threshold pressure, subglottal pressure and phonation, pressure measurement and phonation, lung pressure and phonation, and vocal fold oscillation onset. Inclusion criteria were limited to indirect assessment of phonation threshold pressure, English language publications between 1980 and 2009, and peer-reviewed journals. Studies including animals, computer or physical models, alaryngeal speakers, laryngeal airway resistance, or any airflow interruption technique were excluded. Twenty-four articles matched the inclusionary criteria. An online survey to query task elicitation procedures was then developed from the literature review.
The scientific rationale for inclusion of phonation threshold pressure data was consistent across published studies; however, variations in procedural methodology for task elicitation were identified, as were environmental and participant inconsistencies that might affect phonation threshold pressure values. Findings of the online survey mirrored the inconsistencies identified in the literature review.
The methodological differences for task elicitation identified in this comprehensive review of the literature and the online survey, while bringing into question the reliability of phonation threshold pressure measurement, illuminate scientific questions yet to be answered to further refine and potentially standardize phonation threshold pressure as a more reliable research and clinical measurement.
American Journal of Speech-Language Pathology 08/2011; 20(4):348-66. · 2.45 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 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.
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.
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.
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.
Journal of voice: official journal of the Voice Foundation 04/2011; 26(1):18-23. · 0.95 Impact Factor