Publication Date


Document Type


First Advisor

Shearer, William M.

Degree Name

M.A. (Master of Arts)

Legacy Department

Department of Communicative Disorders


Larynx; Voice


This study was completed to determine the reliability of the s/z ratio for evaluations of laryngeal functioning. Two speech pathologists, known as Clinician A and Clinician B, evaluated 78 first and second grade children in the Sycamore, Illinois, public schools, using the s/z ratio. One-half of the children were tested first by Clinician A, and then retested several days later by Clinician B. The other one-half of the children were tested first by Clinician B, and retested several days later by Clinician A. All children were retested for a third and final time by Clinician A. S/z ratios were computed for all subjects for Test One, Test Two, and Test Three. Mean prolongation times for all s/z ratios were also computed. No significant differences were found between the s/z ratios of first graders and second graders, or between s/z ratios obtained by Clinician A and those obtained by Clinician B. Similarly, there was no significant difference in s/z ratios for Test One versus Test Two. Essentially no relationship was found between prolongation times and s/z ratios. Test Three, however, was found to have significantly smaller s/z ratios than either Test One or Test Two. This latter finding was felt to be related to the high incidence of respiratory infections during that testing period. Results of this study suggest that there is high test-retest reliability and high interclinician reliability in the s/z ratio for evaluating children's laryngeal function.


Bibliography : pages 47-48.


vi, 48 pages




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