unilateral hearing loss- hearing loss occurs in only one ear. in contrast to bilateral hearing loss which occurs in both ears.
American Association of Audiology has clearly defined the limits of minimal hearing losses (Anderson, 2011). The AAA defines three areas which can be considered mild medically:
- Mild—average air conduction between 20-24 dB in both ears
- Unilateral—average air conduction >20dB in impaired ear
- High Frequency—average air conduction >25 at two or more frequencies above 2000kHz
Using the medical definition established at the 2005 National Workshop on Mild and Unilateral Hearing Loss, sponsored by the Center for Disease Control and Prevention, mild bilateral hearing loss or unilateral hearing loss may be described in literature as: ‘mild, minimal, slight, and partial’ hearing losses (Ross et al., 2008).
- Permanent mild bilateral hearing loss—a pure-tone air-conduction threshold between 16-40dB at 500, 1000, and 2000Hz or thresholds greater than 25dB at 2 frequencies above 2000Hz.
- A unilateral hearing loss—pure-tone air-conduction threshold equal to or greater than 20-40dB at 500, 1000, and 2000Hz or thresholds greater than 25dB at 2 frequencies above 2000Hz and thresholds in the good ear less than 15dB (Davis, Reeve, Hind, & Bamford, 2000).