Behavioural tests: applications and limitations in comparison with brainstem response audiometry.

Conditioned behavioural hearing tests cannot be performed in children before the developmental age of 8 months. Informal tests cannot be used as threshold tests as the stimuli are unspecific in frequency, and the observed reactions are not equivalent to the threshold level. Brainstem response audiometry (BRA) was performed on 47 children (23 normal children and 24 children with mental retardation with or without behavioural disturbances) in whom informal test results were unclear. The BRA was followed up by behavioural tests 1 to 10 years later. In none of the cases did the BRA thresholds indicate better hearing function than the actual threshold noted later on at behavioural tests. High BRA thresholds (up to 75 dB nHL) were found in 5 normal-hearing children with serous otitis media at the time of BRA recording.