WHO Ear and Hearing Disorders Survey: Ecuador National Study 2008-2009
Table 4
WHO grades for hearing impairment [17]. Disability of hearing impairment is defined as moderate or worse hearing loss in the better ear (41 dB average thresholds or greater in persons 15 yrs or older, 31 dB or greater in children under 15 yrs). The audiometric ISO values are the averages of values at 500, 1000, 2000, and 4000 Hz.
Grade of impairment
Corresponding audiometric ISO value
Performance
Recommendations
0—no impairment
25 dB or better (better ear)
No or very slight hearing problems. Able to hear whispers.
1—slight impairment
26–40 dB (better ear)
Able to hear and repeat words spoken in normal voice at 1 meter.
Counseling. Hearing aids may be needed.
2—moderate impairment
41–60 dB (better ear)
Able to hear and repeat words spoken in raised voice at 1 meter.
Hearing aids usually recommended.
3—severe impairment
61–80 dB (better ear)
Able to hear some words when shouted into better ear.
Hearing aids needed. If no hearing aids available, lip reading and signing should be taught.
4—profound impairment including deafness
81 dB or greater (better ear)
Unable to hear and understand even a shouted voice.
Hearing aids may help understanding words. Additional rehabilitation needed. Lip reading and sometimes signing essential.
