Authors' objectives: 1. To review the social considerations for the provision of UNHS using Automatic Otoacoustic Emissions (AOAE) and/or Automated Auditory Brainstem Response (AABR) (either alone or in combination) to screen for PCHI in Alberta. 2. To review the published evidence on the efficacy/effectiveness and safety of using AOAE and/or AABR (either alone or in combination) for UNHS. 3. To review the economic literature for the provision of AOAE and/or AABR (either alone or in combination) for UNHS and to determine which screening protocol is cost-effective using an economic model.

Authors' results and conclusions: Information from the Alberta Health and Wellness administrative databases did not allow for an estimation of PCHI prevalence or an analysis of the current age at which children are diagnosed with PCHI in Alberta. A pilot UNHS program from 2001 to December 2004 provided the only Alberta specific PCHI prevalence estimates of 4 per 1000 screened infants. Analyses of Alberta Health and Wellness databases identified a 1998 cohort and found that for children with more than five audiological examinations the median age to first audiological examination was 2 years, with fewer than 25% examined at or before 1 year of age. None of the children with cochlear implants were seen by physicians for hearing loss or received an audiological examination before 6 months of age; the median age at first examination was approximately 1 year. Evidence from two systematic reviews state that: There is good evidence to suggest that AOAE and AABR are equally accurate screening tests for moderate to profound PCHI. A 2-stage protocol using AOAE followed by AABR, may achieve better specificity (>97%) and lower overall referral rates (<2%) than 1 stage protocols using either technology. However, loss to follow-up is a limiting factor for overall program sensitivity. The long-term efficacy/effectiveness of using AOAE and/or AABR for UNHS in terms of improved developmental outcomes is not definitive. The existing evidence that early detection and start of habilitation promotes improved communication and language development in an infant with PCHI is limited. No safety issues or concerns associated with applying the technology AABR and/or AOAE in newborns have been reported. Conclusive evidence regarding the impact of false positives has yet to be established. Another concern is the increased number and impact of false negative results that occur with a multi-stage protocol. Data to directly compare the short- and long-term benefits and harms of UNHS versus those associated with selective screening are lacking. According to the economic evaluation conducted for this review: The 1-stage AABR protocol is more cost effective compared to the 1-stage AOAE protocol, since it has lower costs and greater effectiveness. There is no clear answer on which is the cost effective alternative between the 1-stage AABR protocol and the 2-stage protocol (AOAE followed by AABR). The 2-stage protocol is more effective with higher expected costs when compared to the 1-stage protocol. However, the 2 stage protocol includes a greater number of sequential screens over time, and this increases the number of false negative cases, but decreases the number of false positive cases. The additional cost to correctly identify the hearing status of one additional infant between the two protocols is $7,574.78 (Cdn 2003 $).

Authors' recommendations: This review's findings suggest that: UNHS using AOAE and/or AABR technology (either alone in a 2-stage protocol) is effective in terms of increasing early identification of moderate to profound PCHI and may lead to early intervention in diagnosed infants (before 6 months). The 1-stage screening protocol using AABR is a cost effective alternative to the 1-stage screening protocol using AOAE, which is less accurate and costs more. The 2-stage protocol (using AOAE followed by AABR) is more effective with higher expected costs compared to the 1-stage screening protocol using AABR. It is a value judgment if whether correctly identifying one additional infant is worth the additional cost. If UNHS is implemented, those considering AOAE and/or AABR technologies (either as a 1-stage protocol or a 2-stage protocol) should be aware that: AOAE and/or AABR cannot screen for all types and degrees of PCHI. The screening accuracy of AOAE and/or AABR depends on many factors including the cut-off impairment and the screening protocol used. The efficacy/effectiveness of AOAE and/or AABR in terms of longer-term outcomes may be difficult to establish because developmental outcomes are related to more factors than just the accuracy of the screening technologies. The AOAE and/or AABR technologies are still evolving. This review also leads to several conclusions that are especially relevant to the implementation of Newborn Hearing Screening programs: Alberta data currently collected/reported does not allow for an analysis of prevalence of PCHI or a definitive analysis of the current age of diagnosis of PCHI individuals. The creation of a registry of PCHI individuals would be necessary for the effective evaluation of any form of Newborn Hearing Screening Program. The safety and clinical efficacy of UNHS has not been established by well-designed clinical trials and only limited evidence supports the pivotal assumption of a UNHS program which is that early detection of PCHI leads to more effective habilitation. The available evidence suggests that a UNHS program's effectiveness is lower than efficacy estimates based upon analysis of the technology's characteristics alone. Specific strategies to minimize failure to screen and loss to follow-up are integral in the implementation of UNHS. Although there is limited evidence to suggest that UNHS is superior to selective screening, data that directly compare the short- and long-term benefits and harms of these alternatives is still lacking. Higher false positive rates (and therefore increased audiological assessments) threaten the cost-effectiveness of UNHS over selective screening programs. The weakest link in the evidence chain is the demonstration that earlier detection of individuals not located by a selective screening program will receive more effective habilitation. In view of the widespread adoption of UNHS programs in Canadian provinces, the potential to perform a natural experiment in Alberta to contribute to the evidence base around Newborn Hearing Screening is worth consideration.

Authors' methods: Systematic review

Project Status: Completed

Year Published: 2007

URL for published report: http://www.ihe.ca/advanced-search/screening-newborns-for-hearing

URL for additional information: http://www.health.alberta.ca/initiatives/health-evidence-reviews-list.html

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Institute of Health Economics

Contact Address: 1200, 10405 – Jasper Avenue, Edmonton, AB T5J 3N4, Canada. Tel: +1 780 448 4881 Fax: +1 780 448 0018

Contact Name: info@ihe.ca

Contact Email: info@ihe.ca

Copyright: Institute of Health Economics (IHE)