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Updated: Apr 25, 2026
Systematic Hearing Performance Evaluation Process for Adolescents with Cochlear Implantation at Early Ages
Published on: March 24, 2023
Bilateral cochlear implantation for hearing-impaired children: criterion of candidacy derived from an observational
Rosemary Elizabeth Susan Lovett1, Deborah Anne Vickers, Arthur Quentin Summerfield
11Ear Institute, University College London, London, United Kingdom; and 2Department of Psychology and Hull York Medical School, University of York, York, United Kingdom.
Insights
Children with severe to profound hearing loss may benefit from bilateral cochlear implants. A four-frequency pure-tone average (PTA) of 80 dB HL or poorer indicates candidacy, with a two-frequency PTA of 85 dB HL as an alternative measure.
Area of Science:
- Audiology and Otolaryngology
- Pediatric Hearing Impairment
- Medical Device Technology
Background:
- Defining candidacy criteria for pediatric bilateral cochlear implantation (CI) is challenging.
- Comparing outcomes between bilateral CIs and bilateral hearing aids (HA) is crucial for policy-making.
- Previous criteria for CI candidacy have been based on a 4:1 odds ratio for better outcomes.
Purpose of the Study:
- To compare speech discrimination outcomes in children with bilateral CIs versus bilateral HAs.
- To establish a criterion for pediatric bilateral CI candidacy based on unaided pure-tone average (PTA) hearing levels.
- To determine the PTA threshold at which children have a 4:1 odds of a better outcome with CIs compared to HAs.
Main Methods:
- Observational study of 71 children (46-86 months) with hearing impairment receiving audiological care in the UK.
- Participants were divided into bilateral CI (n=28) and bilateral HA (n=43) groups.
- Speech understanding was assessed using closed-set word discrimination tests in quiet, noise, and babble conditions; actuarial methods were used to compare outcomes.
Main Results:
- A four-frequency PTA of 80 dB HL (mean of 79, 86, 76 dB HL across conditions) was associated with 4:1 odds of better outcomes with CIs.
- A two-frequency PTA of 85 dB HL (mean of 83, 92, 80 dB HL across conditions) was associated with 4:1 odds of better outcomes with CIs.
- These PTA values represent the hearing level threshold for considering bilateral CI candidacy.
Conclusions:
- Children with unaided four-frequency PTA of 80 dB HL or poorer bilaterally should be candidates for bilateral CIs.
- If a four-frequency PTA is unmeasurable, a two-frequency PTA of 85 dB HL or poorer bilaterally should be the criterion.
- Adoption of these criteria could expand CI provision for children in England and Wales.
Objectives:
Policy-makers have struggled to define the minimum degree of hearing impairment at which children should be offered cochlear implants rather than the less invasive alternative of acoustic hearing aids. This study compared outcomes for children with bilateral cochlear implants and children with bilateral hearing aids, to determine a criterion of candidacy for pediatric bilateral cochlear implantation.
Design:
This observational study measured the listening skills of children who received routine audiological care in the United Kingdom. Participants were recruited from hospitals, educational services, and charities. Eligibility criteria included a diagnosis of hearing impairment before 31 months of age and pure-tone thresholds greater than or equal to 50 dB HL at 2 and 4 kHz bilaterally. Seventy-one children participated, aged 46 to 86 months (mean 64 months). Twenty-eight children used bilateral implants provided in a simultaneous surgery; 43 used bilateral digital hearing aids. The two groups of children were demographically similar in variables that predict outcomes for children with hearing impairment. Children's ability to understand speech was measured using closed-set tests of word discrimination in three conditions: in quiet, in pink noise, and in two-talker babble. For each listening test, an actuarial method was used to compare the distribution of scores from children with cochlear implants and children with hearing aids. The aim was to calculate the unaided pure-tone average (PTA) hearing level at which a child has odds of 4:1 of a better outcome with implants than with hearing aids. The PTA associated with odds of 4:1 has been used previously to define criteria of candidacy for implantation. The main analyses used a four-frequency PTA (mean of unaided thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear). Additional analyses used a three-frequency PTA (0.5, 1, and 2 kHz) and two-frequency PTA (2 and 4 kHz).
Results:
Odds of 4:1 of a better outcome with implants were associated with a four-frequency PTA of 79, 86, and 76 dB HL for tests of word discrimination in quiet, noise, and babble, respectively. The mean of these three estimates is 80 dB HL. It can be difficult to measure a four-frequency PTA in young children, but a two-frequency PTA typically can be measured. Odds of 4:1 were associated with a two-frequency PTA of 83, 92, and 80 dB HL for tests of word discrimination in quiet, noise, and babble, respectively. The mean of these three estimates is 85 dB HL.
Conclusions:
Children with an unaided four-frequency PTA of 80 dB HL or poorer in both ears should be considered candidates for bilateral cochlear implantation. In cases where a four-frequency PTA cannot be measured, the criterion of candidacy should be a two-frequency PTA of 85 dB HL or poorer in both ears. If adopted by policy-makers, these recommendations would expand the provision of cochlear implants among children in England and Wales.
