Behaviour better than the ABR

Vignette

A 9-month-old is tested with visual reinforcement audiometry in sound field. The tester records apparent responses at soft levels, but an earlier tone-burst ABR had estimated a moderate-to-severe loss.

Test findings

Sound-field VRA suggests near-normal responses, discordant with the ABR estimate of a moderate-to-severe loss.

Diagnostic question

How should this discrepancy be approached?