In April 2013 there was a conference in the UK where the results of the National Paediatric Bilateral Cochlear Implant Audit were presented. The papers from this conference are due to be published in August. However Dr Nina Sawicki attended and has provided 2ears2hear a copy of her Conference Report. This is a sneak peek at what will be published later this year.

In 2009 the United Kingdom issued ground breaking guidelines to its hospital system that stipulated the strong preference to simultaneously implant children who can medically benefit from bilateral Cochlear Implants. It also stipulated that children (0-18yo) who currently had one Cochlear Implant were to be offered a second (subject to it being medically appropriate). An audit was commissioned to measure progress against those guidelines and to measure outcomes.

To clarify, an audit is a study of the entire population. Typically a study takes a sample of the population and controls for various variables. In this case this audit looked at the entire 1,001 children across 14 different implant programmes. These were made up of 536 sequentially implanted children (the second implant was installed later) and 465 simultaneously implanted children (the second implant was installed during the same operation as the first). So the data that was analysed was considerable and robust.

There were some key findings of the audit presented at the conference.


There was no difference in clinical safety between unilateral, sequential bilateral or simultaneous bilateral surgeries. Major complications were 1.6% and minor complications we 6.5%. These are very acceptable rates.


A number of tests were undertaken. A clear pattern emerges from these tests.

  • Bilateral children significantly outperform unilateral children
  • Simultaneously implanted children outperform sequentially implanted children
  • The longer the gap between first and second implants, the poorer the outcome (although it is still better than unilateral)

These results are consistent with all recent research.

One significant result was in the British Picture Vocabulary Scale (BPVS) test. This is a norm referenced test (meaning its been used on normal hearing kids and calibrated to their levels – a bit like National Standards in New Zealand). If an average result is 100, bilateral children achieve between 85 and 115 within one year of switch on (ie. within one standard deviation, on average). Unilaterally implanted children are achieving less than 80 after three years (on average)

This is a truly appalling result. While there are always children who will do well with just one Cochlear Implant, this data says that they are very much the exception. The data is also suggesting that they do not catch up given more time (and expensive therapy resource). In New Zealand therapy for a Cochlear Implant child can cost between $30-50,000 a year (the price of a second Cochlear Implant). Bilateral children, on the other hand, catch up with their normal hearing peers quite quickly.

We have previously highlighted the New Zealand Ministry of Health’s position that unilateral implants allow “…most children to develop their language skills at the crucial early stage.” The National Bilateral Cochlear Implant Audit categorically denounces this position.

At 2ears2hear we believe it is now no longer accurate nor ethical for the Ministry of Health to continue with their assertions about the effectiveness of unilateral implants. In fact we believe it is now unethical to continue to only offer unilateral implants to children. 2ears2hear have proposed an approach to funding bilateral implants that will cost around $1m per year. Given the knowledge of these results, it is now a matter of urgency for funding to be found.

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