An improved procedure for assessing ABR latency in young subjects based on a new normative data set.

Auditory brainstem response (ABR) latencies in normal young and very young subjects are longer than in mature subjects. Use of adult norms in the assessment of young subjects may therefore result in the erroneous reporting of abnormalities in subjects who are in no way impaired. In this study a new normative data set was established by measuring ABR absolute and interpeak latencies in 374 subjects in different age groups with normal ABR and no risk factor for hearing impairment or neurological abnormality. Double exponential functions were fitted to a number of latency measures derived from the data and from those functions a table of correction values was computed. The variability in the measurements of the children is greater than that of the adults. Procedures are proposed which enable the assessment of abnormality of ABR latencies to be made for all subjects regardless of age.