Neonatal Hearing Screening
Universal screening, the 1-3-6 rule, and the structural reason OAE-based programmes miss ANSD.
The 1-3-6 rule
The JCIH 2019 framework: screen by 1 month, diagnose by 3 months, intervene by 6 months[20]. The rationale is the neuroplasticity window for spoken-language acquisition; interventions started later have measurably poorer speech-and-language outcomes.
| Target | Value |
|---|---|
| Screen by | 1 month |
| Diagnose by | 3 months |
| Intervene by | 6 months |
| Coverage | ≥ 95% |
| Refer rate | < 4% |
| Loss-to-follow-up | < 20% |
AABR vs OAE
OAE screens probe outer hair-cell function. A pass requires intact OHCs and a working middle ear. They are quick, cheap, and miss ANSD. AABR screens deliver a fixed 35 dB nHL stimulus and apply an algorithmic pass/refer decision on the recorded response. They detect ANSD because they sample the neural response itself[21].
NICU protocol
JCIH recommends AABR (not OAE) for all NICU graduates. The NICU population has a much higher prevalence of ANSD — hyperbilirubinaemia, hypoxia, and ototoxic medications all favour synaptopathic phenotypes that OAE-based screens would miss.
Risk indicators
Children passing the screen but with a risk indicator (family history of permanent childhood hearing loss, congenital CMV, craniofacial anomalies, syndromes associated with hearing loss, postnatal meningitis, NICU > 5 days) require ongoing audiologic surveillance — at least one diagnostic audiologic assessment by 9 months. Passing the screen does not equal lifetime normal hearing[9].
Programme quality metrics
Coverage above 95% of births, refer rate below 4%, and loss-to-follow-up below 20% are the JCIH operational targets. Loss-to-follow-up is consistently the hardest one — missed diagnoses cluster in families who skipped or never returned for confirmatory testing.
What the screen does not do
Newborn screens estimate hearing at 35 dB nHL. They do not quantify mild loss, do not assess CAPD or higher cortical function, and do not pick up late-onset losses. A passed screen is reassuring at one moment in time. Hearing thresholds in children are dynamic; vigilance continues.