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Listening to speech in competing sounds poses a major difficulty for children with impaired hearing. This study aimed to determine the ability of children (3-12 yr of age) to use spatial separation between target speech and competing babble to improve speech intelligibility. Fifty-eight children (31 with normal hearing and 27 with impaired hearing who use bilateral hearing aids) were assessed by word and sentence material. Speech reception thresholds (SRTs) were measured with speech presented from 0° azimuth, and competing babble from either 0° or ±90° azimuth. Spatial release from masking (SRM) was defined as the difference between SRTs measured with co-located speech and babble and SRTs measured with spatially separated speech and babble. On average, hearing-impaired children attained near-normal performance when speech and babble originated from the frontal source, but performed poorer than their normal-hearing peers when babble was spatially separated from target speech. On average, normal-hearing children obtained an SRM of 3 dB whereas children with hearing loss did not demonstrate SRM. Results suggest that hearing-impaired children may need enhancement in signal-to-noise ratio to hear speech in difficult listening conditions as well as normal-hearing children.

Speech intelligibility of mild and moderately hearing‐impaired listeners can be successfully accounted for in terms of audibility, as quantified by the articulation index theory. For people with more severe losses, performance is often overestimated by audibility. It is hypothesized that deficits in frequency and temporal resolution may be responsible for the reduced ability of these listeners in using an audible signal for speech intelligibility. This study aimed to measure the amount of information that could be extracted from an audible signal by listeners with different degrees of hearing loss at different frequency regions. Twelve normally hearing and 40 hearing‐impaired listeners were tested using filtered sentence material presented at different levels. The results showed that some listeners performed better than normal at low sensation levels but much poorer at high sensation levels. The conventional method of modifying the index by a multiplicative factor would not be appropriate because for many subjects, a smaller factor would be needed at high than at low sensation levels. A modification procedure which incorporates a level‐dependent and frequency‐dependent correction is proposed, and is verified using speech results obtained from sentences and nonsense syllables tests.