Summary of Systematic Review
|Universal Neonatal Hearing Screening|
Merlin, T., Hedayati, H., et al. (2007).
Adelaide: Adelaide Health Technology Assessment (AHTA), MSAC reference 17 Assessment Report, 266 pages.
This review meets the criteria for a high-quality evidence-based systematic review.
Indicators of Review Quality:
|The review states a clearly focused question or aim||Yes|
|Criteria for inclusion of studies are provided||Yes|
|Search strategy is described in sufficient detail for replication||Yes|
|Included studies are assessed for study quality||Yes|
|Quality assessments are reproducible||Yes|
|Characteristics of the included studies are provided||Yes|
This is a review of the literature examining the prevalence of permanent childhood hearing loss (PCHL), the diagnostic accuracy of hearing screening tests used for universal newborn hearing screening (UNHS), and the safety, effectiveness and cost-effectiveness of UNHS.
- What is the prevalence of PCHL in neonates in Australia?
- What is the diagnostic accuracy of tests for PCHL in neonates?
- Does UNHS affect the clinical management of PCHL in infants?
- Does UNHS have an impact on adverse outcomes associated with PCHL?
Infants with PCHL.
Universal newborn hearing screening.
Number of Studies Included:
Permanent Childhood Hearing Loss
- General Findings
- No physical harm resulting from UNHS was reported in any of the studies. Some studies suggested that there was a "slight increase in anxiety and depression in mothers if their infant received a negative screening test, but these states remained within the normal ranges, and as such no clinically important differences were identified" (p. 150).
- Based on the literature, referral, diagnosis, and management of PCHL happens earlier and more frequently with UNHS than without it.
- The evidence indicates that children identified through UNHS have increased receptive language abilities however the evidence for improved expressive language abilities or overall communicative abilities is unclear. Data on the impact of UNHS on longer-term outcomes such as education and employment have not yet been reported.
- "From the available literature it can be concluded that, in the short term, the costs for the additional cases identified and diagnosed by UNHS are greater per unit than those of targeted screening. However, taking a societal perspective over the long term suggests that identifying a larger proportion of hearing impaired children at an early stage (i.e., < 6 months of age) would result in a cost saving over all" (p. 151).
- The accuracy of transient evoked otoacoustic emissions (TEOAE) testing is affected by ambient noise. In quiet environments, TEOAE has been noted to have sensitivity up to 100% and specificity of 92%. However, the positive predicative value (1.5%) of an initial TEOAE test to correctly diagnose PCHL is very low. This is likely due to "the frequency of transient hearing losses in newborns due to ear occlusion and the low prevalence [of PCHL]" (p. ix).
- Early model automated auditory brainstem response (AABR) tests have a reported sensitivity of 80% and specificity of 92%. The positive predictive value of the test (2.2%) was considered low however experts note that later model AABR tests may have improved diagnostic accuracy.
- False positive rates of either test (i.e., TEOAE or AABR) may be minimized with the introduction of a second or third stage screen prior to diagnostic testing. "This may, however, result in unnecessary caregiver anxiety and added costs and delays in rehabilitation" (p. ix).
Adelaide Health Technology Assessment (Australia)
Early Hearing Detection and Intervention, Deafness, Hearing Loss