Probe-tube microphone measures in hearing-impaired children and adults.

Boys Town National Institute for Communication Disorders in Children, Omaha, Nebraska.
Ear and Hearing (Impact Factor: 3.26). 11/1988; 9(5):243-7. DOI: 10.1097/00003446-198810000-00003
Source: PubMed

ABSTRACT This study was designed to investigate the reliability of real-ear measurements of sound pressure level (SPL) and to compare these values with two coupler measures of SPL. A commercially available probe tube microphone system was used to measure real ear SPL in both children and adults. Test-retest reliability decreased as a function of frequency for both groups and, in general, was slightly poorer for the children. For both groups, coupler to real ear differences were larger for the 2 cm3 coupler than for the reduced volume coupler; however, no significant differences were observed between groups. In addition, a measure of ear canal volume was not found to be a good predictor of coupler to real ear discrepancies.

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