OAE Test for Newborn Hearing Screening
The OAE (otoacoustic emissions) test is a noninvasive physiologic screening method that uses a sensitive microphone within a small probe placed in the ear canal to detect acoustic signals generated by the cochlear outer hair cells in response to auditory stimuli (clicks or tone bursts), providing automated pass-fail results within approximately 10 minutes without requiring test interpretation by an audiologist. 1
How the Test is Performed
The procedure is straightforward and infant-friendly:
- A small probe containing both a speaker and sensitive microphone is placed in the infant's ear canal 2
- The probe delivers acoustic stimuli (either clicks or tone bursts) to the cochlea 1
- The microphone records the cochlear responses—acoustic signals that travel in reverse direction from the cochlea through the middle ear space and tympanic membrane back to the ear canal 2, 1
- The automated device provides a pass-fail report using statistical probability for automated response detection 1
- Testing takes approximately 10 minutes and can be performed whether the infant is asleep or awake 2
- The infant must remain relatively inactive during testing to avoid motion artifacts 2
What the Results Indicate
Pass Result
- Indicates normal cochlear outer hair cell function 1
- Reflects intact peripheral auditory system extending to the cochlear outer hair cells 1
- Negative predictive value is very high (99.7% in one study) 3
Fail/Refer Result
A failed OAE screening does not automatically mean permanent hearing loss. Multiple factors can cause failure:
Transient/Benign Causes:
- Outer or middle ear dysfunction (fluid, vernix, cerumen) 2, 1
- These transient conditions may result in "failed" screening despite normal cochlear function 1
True Hearing Loss:
- Cochlear (sensory) hearing loss affecting outer hair cells 1
- Sensitivity for detecting hearing impairment ranges from 46-67% depending on the population 3, 4
Critical Limitations and Pitfalls
The most important caveat: OAE testing cannot detect auditory neuropathy/dyssynchrony or neural conduction disorders of the eighth nerve or auditory brainstem pathway. 1 Because OAEs are generated within the cochlea, neural dysfunction without concomitant sensory dysfunction will be completely missed by OAE screening alone.
Additional limitations include:
- Very sensitive to middle ear effusions and debris in the ear canal 2
- Does not assess cortical processing of sound—not a comprehensive hearing test 2
- May miss mild or isolated frequency-region hearing losses 1
- Lower sensitivity in high-risk populations, particularly preterm infants ≤34 weeks (sensitivity only 46% in one study) 4
- Referral rates vary widely (1.3% to 39%) depending on protocol, timing, and frequencies tested 5
Clinical Implications for Screening Programs
For well infants in regular nurseries: OAE alone is acceptable for initial screening 1
For NICU infants and high-risk populations: Automated ABR should be used instead of or in addition to OAE because these infants have higher risk of auditory neuropathy spectrum disorders that OAE cannot detect 1, 4
All infants who fail OAE screening require diagnostic ABR (BERA) for confirmation, as OAE has relatively low positive predictive value (33-56%) 3, 6. The high false-positive rate is primarily due to transient middle ear conditions in newborns.
Strategies to improve OAE performance include delaying initial screening beyond the first 24 hours, performing retests before referral, and using higher frequency protocols 5.