Table 1.

Ototoxicity criteria with inclusion of high frequency audiometry

Grade	Chang grading system	Tune grading system
0	≤20 dB at 1, 2, and 4 kHz	No hearing loss
1a	≥40 dB at any frequency 6 to 12 kHz	Threshold shift ≥10 dB at 8, 10 and 12.5 KHz
1b	>20 and <40 dB at 4 kHz	Threshold shift ≥10 dB at 1, 2 and 4 KHz
2a	≥40 dB at 4 kHz and above	Threshold shift ≥20 dB at 8, 10 and 12.5 KHz
2b	>20 and <40 dB at any frequency below 4 kHz	Threshold shift ≥20 dB at 1, 2 and 4 KHz
3	≥40 dB at 2 or 3 kHz and above	≥35 dB HL at 1, 2 and 4 KHz
4	≥40 dB at 1 kHz and above	≥70 dB HL at 1, 2 and 4 KHz
ASHA	≥20 dB decrease in pure tone thresholds at any test frequency OR ≥10 dB decrease at two adjacent frequencies
	OR decreased response at three consecutive test frequencies where responses were previously obtained

ASHA emphasizes baseline evaluation for early identification of ototoxicity and Chang/Tune emphasizes documenting high frequency audiometric thresholds and grading of hearing loss. Therefore, a combination of the ASHA and Chang/Tune classifications is recommended as best practice for early identification and subsequent monitoring of ototoxicity. ASHA: American Speech-Language-Hearing Association, HL: hearing level.