Age effects and normative data on a Dutch test battery for auditory processing disorders.

A test battery compiled to diagnose auditory processing disorders (APDs) in an adult population was used on a population of 9-16-year-old children. The battery consisted of eight tests (words -in noise, filtered speech, binaural fusion, dichotic digits, frequency and duration patterns, backward masking, categorical perception, digit span) and a questionnaire. Descriptive statistics were computed on data obtained from 75 children from primary school (age 9-12 years) and 30 adolescents from secondary school (age 14-16 years) with normal hearing and normal intelligence. Most test scores did not follow a normal distribution. Age effects were present in most tests, within the group as well as when children and adolescents were compared to adults. This suggests that maturation of auditory processing abilities takes place even during adolescence. Relative measures regarding ear differences and binaural versus monaural scores did not appear to be age-related. These measures might be useful in diagnosing APD, supplementary to the absolute measures. Factor analysis showed four components that address underlying processes. However, these results must be interpreted cautiously because the study did not include any subjects with APD.