Development of ABR parameters in a preterm and a term born population.

Auditory brain stem responses were recorded in full term infants (N = 465) and in unselected preterm infants (N = 178) who were tested in, respectively, 10 and 12 age groups from birth until 5 yr. The latencies of waves I and V as well as the wave I-wave V delay and the wave V to wave I amplitude ratio were compared at the various age groups. It was found that the mean absolute latency values in the preterm group were significantly longer than for the full term group up to about 2 yr of age. In contrast, the I-V delay and the amplitude ratio were not different. It is concluded that prematurity does not cause a different rate of maturation for the ABR compared to full term infants. In addition, it is suggested that the differences in absolute latencies can be explained on the basis of a higher incidence of otitis media in the preterm population.