The LISN-S provides a quick, objective method of measuring a child's ability to understand speech in background noise. The small degree of inter- and intra-participant variation in the 5- and 6-yr-old children suggests that the test is capable of assessing auditory processing in this age group. However, because there appears to be a strong developmental curve in binaural processing skills in the 5-yr-olds, it is suggested that the LISN-S be used clinically with children from 6 yr of age. Cut-off scores, calculated as 2 standard deviations below the mean adjusted for age, were calculated for each performance measure for children ages 6 to 11 yr. These scores, which represent the level below which performance on the LISN-S is considered to be outside normal limits, will be used to in future studies with children with suspected central auditory processing disorder.

All hearing-impaired people will have a spatial processing deficit of some degree. This should be given due consideration when counseling patients in regard to realistic expectations of how they will perform in background noise. Further research is required into potential remediation for spatial-processing deficits and the cause of these deficits.

The study supports the hypothesis that a high proportion of children with suspected (C)APD have a deficit in the mechanisms that normally use the spatial distribution of sources to suppress unwanted signals. The LISN-S is a potentially valuable assessment tool for assessing auditory stream segregation deficits, and is sensitive in differentiating various forms of auditory streaming.

As there was no significant difference among adults aged 18-60 yr on the LiSN-S talker, spatial, and total advantage measures, it appears that the decline in ability to understand speech in noise experienced by 50- to 60-yr-olds is not related to their ability to use either spatial or pitch cues. This result suggests that some other factor/s contributes to the decline in speech perception in noise experienced by older adults that is reported in the literature and was demonstrated in this study on the LiSN-S low and high cue SRT measures.