Paediatric cochlear implantation and health-technology assessment

Cochlear implants are provided to children on the basis of the hypothesis that short-term outcomes in auditory receptive skills will translate via a cascade of medium-term outcomes into greater social independence and quality of life. The medium-term outcomes include: (i) enhanced engagement and integration in primary education, leading to greater scholastic achievement; (ii) enhanced social versatility and robustness, permitting a successful transition to secondary education; and (iii) enhanced educational qualifications, allowing greater opportunities in further education and employment. A sufficient number of children have used implants for long enough for it to be feasible to establish whether the first two medium-term outcomes are being achieved and, if so, at what cost in the provision of health care and education. The first part of this paper discusses alternative research designs that could address these issues. Although a prospective randomised controlled trial would provide the most powerful evidence for or against the hypothesis, it is implausible that adequate compliance with randomisation to treatments could be sustained to give such a study sufficient power. The most powerful realisable design would be a large-scale cross-sectional comparison of implanted children and matched groups of their non-implanted peers. The second part of the paper describes the results of a speculative cost-benefit analysis that seeks to identify the cost to society of providing implants to children. The analysis is based on measured costs of health care, but on estimates of costs and cost-savings in other domains. It indicates that paediatric implantation could be cost-neutral in the UK, provided that implantation saved £3000/year in the cost of education, £1000/year in other domains, and permitted an increase in personal income of 25% of the national median household income. These savings might be realised if implantation permitted sufficient facility in spoken language to allow every implanted child to enter mainstream education.