18Putting the battery together
A pile of test results is not a diagnosis. The skill the whole chapter has been building toward is synthesis: taking the audiogram, the masked thresholds, the air–bone gap, the speech scores, the tympanogram and reflexes, the emissions and the evoked potentials, and fitting them into a single picture that hangs together. When it does, the type, degree, configuration and site of the loss fall out, and so does a quieter but vital judgement — that the result is valid. When it does not, the disagreement points to the next step rather than to a number to be accepted. Each site of lesion leaves a recognisable fingerprint across the battery, and learning to read those fingerprints at a glance is what turns a technician into a diagnostician. This closing module assembles the toolkit and hands its conclusions to the candidacy decision.
FOne consistent picture
A complete evaluation synthesises the audiogram, masked thresholds, the air–bone gap, speech audiometry, immittance/reflexes, OAEs and evoked potentials into one internally consistent picture, applying the cross-check principle throughout. Discrepancies drive the next step — re-test, add a cross-check, or reinterpret — rather than accepting any single number.[1976]
TThe classic fingerprints
The recognisable patterns: conductive (gap + absent ipsilateral reflex + flat tympanogram); cochlear (no gap, recruitment, OAEs absent past ~35 dB, reflexes elevated); retrocochlear (rollover, reflex decay, prolonged ABR I–V); and auditory neuropathy (present OAE/CM with absent neural ABR and absent reflexes).
CAdult & paediatric streams
The two streams differ in emphasis. The adult stream leans on masked pure tones, recorded speech at 60 dBA, immittance, and evoked potentials only where validity is doubtful. The paediatric stream is built on ABR/ASSR plus developmentally appropriate behavioural and parent-report measures — but both rest on the same cross-check logic.[2020]
TThe hand-off to candidacy
The battery yields the type, degree, configuration and site of the loss, the validity of the result, and the aided-audibility picture — exactly the inputs a candidacy decision needs. The toolkit measures hearing; the next chapter applies it — best-aided sentence testing, the 60/60 rule, regulatory device cutoffs and the multidisciplinary judgement that the implant will beat the best aids (Chapter 11). Fixed protocols, interlist-equivalent materials and calibrated equipment make the results trackable across sessions and ready to feed outcome monitoring.
What is the site of lesion?
Which fingerprint indicates a cochlear sensorineural loss?
What does the assembled battery hand to the candidacy decision?