Quasi-output-cost-ratio, perceived voice quality, and subjective evaluation in female kindergarten teachers

Abstract

This study estimated vocal economy and investigated its relation to perceived voice quality and self-reported symptoms of vocal fatigue in kindergarten teachers. Quasi-output-cost ratio (QOCR) was calculated for sustained vowel [a:] at habitual loudness and at sound pressure level (SPL) of 90 dB_6cm. QOCR was calculated as (SPL/CQ_EGG) × T/T₀, where CQ_EGG is the contact quotient measured from the electroglottogram, T is the period length, and T₀ is arbitrarily set mean period length (0.005 s in females). QOCR correlated negatively with perceived firmness at standard SPL and with the evaluation of too high pitch for the subject at both SPLs. QOCR did not predict self-reported vocal fatigue. Further studies with connected speech and objectively stated loading symptoms are warranted.

Key words::

• EGG
• perceptual evaluation
• QOCR
• self-evaluation
• vocal economy
• vocal fatigue

Acknowledgements

This study was supported by the Academy of Finland (grant No. 1128095). The authors would especially like to thank laboratory technician Mr Jarmo Helin for assisting in the analyses of the material and Mrs Virginia Mattila, MA, for language correction of the manuscript.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.