Table IV. Auditory test findings and interpretation.

Test	Finding	Number of ears (percentage)	Interpretation
Tympanometry – Middle ear function
	Normal	55/74 (74.3%)	Normal middle ear function
	Negative Pressure	9/74 (12.2%)	Eustachian tube dysfunction
	Flat – Normal volume	1/74 (1.4%)	Stiff middle ear system
	Flat – Large volume	9/74 (12.2%)	Patent ventilation tube
DPOAE – Cochlear OHC function
	Present: broad range	12/64 (18.8%)	Intact OHC function
	Present: limited range	3/64 (4.7%)	Partial OHC function
	Absent*	46/64 (71.8%)	OHC dysfunction
	Noisy	3/64 (4.7%)	Uninterpretable
ABR – Auditory nerve and auditory brainstem function
	Normal latencies	48/60 (80%)	Normal auditory nerve/auditory brainstem function
	Borderline abnormal**	5/60 (8.3%)	Attributable to degree of HL
	Delayed interpeak latencies	6/60 (10%)	Retrocochlear
	Absent	1/60 (1.6%)	Attributable to degree of HL

Data are presented as number of ears (%);

^*an additional eight ears with absent DPOAEs and abnormal tympanometry were not included in this count as indicative of OHC dysfunction;

^**borderline abnormalities included absent waves I or III (n=4 ears) and delayed wave III with all other findings normal (n=1); DPOAE, distortion product otoacoustic emission; OHC, outer hair cells; ABR, auditory brainstem response; HL, hearing loss