Acceptable noise levels in preschool children with normal hearing

The acceptable noise level (ANL) measure is an indicator of hearing aid use. The majority of research in this area has focused primarily on adults. Research using school-aged listeners, specifically 8 and 12 yr old children, demonstrated that the average ANL values, standard deviations (SDs), and distribution of ANL values for these children were similar to those of adult listeners. Additionally, the ANL measure is reliable over time, even in school-aged listeners. Although ANL values from adult and school-aged listeners have been investigated, no research to date has been conducted using preschool children.

The purpose of the present study was to determine if ANLs could be obtained in preschool children, aged 4 and 5 yr, with normal hearing. This study also aimed to investigate the reliability and distribution of ANL measurements from preschool children, as well as any effect that background noise might present in the listening environment.

Seated in a sound-treated test suite, listeners were tasked with adjusting speech stimuli to their most comfortable listening level; then, with speech present, listeners were tasked with adjusting the background noise to their most acceptable background noise level. Three trials of each measure were averaged and were used to calculate each listener's ANL.

ANLs were attempted on 23 children, ages 4 yr (N = 14) to 5 yr (N = 9), with normal hearing.

Less than half of the 4 yr old listeners performed the ANL task, whereas all of the 5 yr old listeners completed the task successfully. Good test-retest reliability was found for those preschool children who were able to complete the task. Mean ANLs, SDs, ranges, and distributions demonstrated that these values agree with ANL data collected from older school-aged listeners.

Although ANL values were reliably measured in all of the 5 yr old listeners, this was not the case for 4 yr old listeners. ANL values were not reliably obtained from 4 yr old listeners; however, the ANL procedure is appropriate for use for 5 yr old listeners. Furthermore, ANL means, SDs, ranges, and distributions were in agreement with those from older school-aged children and adults, and ANLs in preschool listeners were unaffected by the type of background noise stimuli.