If bone conduction thresholds are worse than air conduction at a given frequency, what should be investigated?

When bone conduction thresholds are worse than air conduction at a given frequency, it suggests there may be a problem with the testing methodology rather than an inherent issue in the patient's auditory system. Specifically, inaccurate placement of the oscillator can lead to misleading results in bone conduction testing.

Proper positioning is crucial for effective stimulation of the cochlea via bone conduction, as it determines how well the sound vibrations are transmitted through the skull. If the oscillator is not placed correctly, it can cause weaker bone conduction thresholds. This would lead to erroneously concluding that the bone conduction hearing is worse than air conduction, thereby prompting a need to first investigate the technique used in conducting the test.

Examining middle ear functionality, patient fatigue, or cochlear health may be relevant in different contexts but do not directly explain a scenario where bone conduction results appear poorer than air conduction due to potential procedural errors. Thus, the need to review the accuracy of the oscillator's placement becomes paramount in this situation.