Paula C. Stacey

Hearing-impaired children in the United Kingdom, I : auditory performance, communication skills, educational achievements, quality of life, and cochlear implantation

Objectives: The objectives of this study were to identify variables that are associated with differences in outcome among hearing-impaired children and to control those variables while assessing the impact of cochlear implantation. Study Design: In a cross-sectional study, the parents and teachers of a representative sample of hearing-impaired children were invited to complete questionnaires about children’s auditory performance, spoken communication skills, educational achievements, and quality of life. Multiple regression was used to measure the strength of association between these outcomes and variables related to the child (average hearing level, age at onset of hearing impairment, age, gender, number of additional disabilities), the family (parental occupational skill level, ethnicity, and parental hearing status), and cochlear implantation. Results: Questionnaires were returned by the parents of 2858 children, 468 of whom had received a cochlear implant, and by the teachers of 2241 children, 383 of whom had received an implant. Across all domains, reported outcomes were better for children with fewer disabilities in addition to impaired hearing. Across most domains, reported outcomes were better for children who were older, female, with a more favorable average hearing level, with a higher parental occupational skill level, and with an onset of hearing-impairment after 3 years. When these variables were controlled, cochlear implantation was consistently associated with advantages in auditory performance and spoken communication skills, but less consistently associated with advantages in educational achievements and quality of life. Significant associations were found most commonly for children who were younger than 5 years when implanted, and had used implants for more than 4 years. These children, whose mean (preoperative, unaided) average hearing level was 118 dB, were reported to perform at the same level as nonimplanted children with average hearing levels in the range from 80 dB to 104 dB, depending on the outcome measure. Conclusions: When rigorous statistical control is exercised in comparing implanted and nonimplanted children, pediatric cochlear implantation is associated with reported improvements both in spoken communication skills and in some aspects of educational achievements and quality of life, provided that children receive implants before 5 years of age.

Face processing and familiarity: evidence from eye-movement data

How is information extracted from familiar and unfamiliar faces? Three experiments, in which eye-movement measures were used, examined whether there was differential sampling of the internal face region according to familiarity. Experiment 1 used a face familiarity task and found that whilst the majority of fixations fell within the internal region, there were no differences in the sampling of this region according to familiarity. Experiment 2 replicated these findings, using a standard recognition memory paradigm. The third experiment employed a matching task, and once again found that the majority of fixations fell within the internal region. Additionally, this experiment found that there was more sampling of the internal region when faces were familiar compared with when they were unfamiliar. The use of eye fixation measures affirms the importance of internal facial features in the recognition of familiar faces compared with unfamiliar faces, but only when viewers compare pairs of faces.

Hearing-impaired children in the United Kingdom, IV: cost-effectiveness of pediatric cochlear implantation

Objective: To estimate the cost-effectiveness of pediatric cochlear implantation by conducting a cost-utility analysis from a societal perspective. Design: In a cross-sectional survey, the parents of a representative sample of hearing-impaired children assessed the health utility of their child using a revised version of the Health Utilities Index Mark III questionnaire. Linear regression was used to estimate the gain in health utility associated with implantation while controlling for eight potentially confounding variables: average (4-frequency, unaided, preoperative) hearing level (AHL), age at onset of hearing-impairment, age, gender, number of additional disabilities, parental occupational skill level, ethnicity, and parental hearing status. The gain in health utility was accumulated to estimate the number of quality-adjusted life years (QALYs) that would be gained from implantation over 15 yr and over a child’s lifetime. The incremental societal cost of implantation, calculated in euros (&U20AC;) at 2001/2 levels, was estimated by summing the incremental costs of implantation that are incurred in the health sector, in the education sector, and by the child’s family. The cost-effectiveness of cochlear implantation was estimated by calculating the incremental societal cost per QALY gained and was compared with an upper limit of acceptability of &U20AC;50,000 per QALY. Results: The parents of 403 implanted children, and 1863 nonimplanted children, completed the health utility questionnaire. Higher health utility was associated with a more favorable AHL, an older age at onset of hearing impairment, female gender, having fewer additional disabilities, having parents with a greater occupational skill level, white ethnicity, and implantation. The gain in health utility associated with implantation was estimated to be higher for children with a worse preoperative AHL and who were implanted when younger. Over 15 yr, for a child implanted at age 6 with a preoperative loss of 115 dB, 2.23 QALYs were estimated to be gained, compared with a mean incremental societal cost of &U20AC;57,359, yielding a mean cost per QALY of &U20AC;25,629. Cost-effectiveness was more favorable: (1) when estimated over a child’s lifetime rather than 15 yr, (2) for children with a worse preoperative AHL, and (3) for children who were implanted when younger. Conclusions: The mean cost of gaining a QALY for the children in the present sample falls within acceptable limits. The strategy of giving highest priority for implantation to children with the greatest loss of hearing, and who are younger, maximizes benefit for a given cost.

Effectiveness of computer-based auditory training for adult users of cochlear implants

Abstract Cochlear implantation is effective at restoring partial hearing to profoundly deaf adults, but not all patients receive equal benefit. The present study evaluated the effectiveness of a computer-based self-administered training package that was designed to improve speech perception among adults who had used cochlear implants for more than three years. Eleven adults were asked to complete an hour of auditory training each day, five days a week, for a period of three weeks. Two training tasks were included, one based around discriminating isolated words, and the other around discriminating words in sentences. Compliance with the protocol was good, with eight out of eleven participants completing approximately 15 hours of training, as instructed. A significant improvement of eight percentage points was found on a test of consonant discrimination, but there were no significant improvements on sentence tests or on a test of vowel discrimination. Self-reported benefits were variable and generally small. Further research is needed to establish whether auditory training is particularly effective for identifiable sub-groups of cochlear-implant users. Sumario La implantación coclear es efectiva para restaurar desde una alteración parcial de la audición hasta una sordera profunda en adultos, pero no todos los pacientes reciben el mismo beneficio. El presente estudio evalúa la efectividad de un paquete de entrenamiento computarizado y auto-administrado que se diseñó para mejorar la percepción del lenguaje en adultos que han utilizado implantes cocleares por más de tres años. Se le pidió a once adultos que completaran una hora de entrenamiento auditivo cada día, cinco dóas por semana, por un peróodo de tres semanas. Se incluyeron dos tareas de entrenamiento, una basada en la discriminación de palabras aisladas y la otra en discriminación de palabras en medio de frases. El cumplimiento del protocolo fue bueno, con ocho de quince participantes que completaron aproximadamente 15 horas de entrenamiento, como se instruyó. Se encontró una mejoría significativa de ocho puntos porcentuales en una prueba de discriminación de consonantes, pero no existió una mejoría significativa en las pruebas de frases o en la prueba de discriminación de vocales. Los beneficios auto-reportados fueron variables y generalmente pequeños. Se requiere investigación adicional para establecer si el entrenamiento auditivo es particularmente efectivo en subgrupos identificables de usuarios de implantes cocleares.

The efficacy of auditory perceptual training for tinnitus: a systematic review

Auditory perceptual training affects neural plasticity and so represents a potential strategy for tinnitus management. We assessed the effects of auditory perceptual training on tinnitus perception and/or its intrusiveness via a systematic review of published literature. An electronic database search using the keywords ‘tinnitus and learning’ or ‘tinnitus and training’ was conducted, updated by a hand search. The ten studies identified were reviewed independently by two reviewers, data were extracted, study quality was assessed according to a number of specific criteria and the information was synthesised using a narrative approach. Nine out of the ten studies reported some significant change in either self-reported or psychoacoustic outcome measures after auditory training. However, all studies were quality rated as providing low or moderate levels of evidence for an effect. We identify a need for appropriately randomised and controlled studies that will generate high-quality unbiased and generalisable evidence to ascertain whether or not auditory perceptual training has a clinically relevant effect on tinnitus.

Hearing-impaired children in the United Kingdom, II: Cochlear implantation and the cost of compulsory education

Objective: The objective of this study was to estimate the impact of cochlear implantation on the cost of compulsory education of hearing-impaired children in the United Kingdom. Study Design: In a cross-sectional survey, teachers were asked to report the school placement of, and amount of support provided to, a representative sample of hearing-impaired children. Costs of school placement were obtained from published sources. Costs of support were calculated from a survey of 11 special education services. The annual education cost (in &U20AC;uros at 2001/2002 levels) of each child was calculated by summing the placement and support costs. Linear regression analyses calculated the association between annual education cost and possession of an implant while controlling nine other variables: average (unaided, preoperative) hearing level (AHL), age at onset of hearing impairment, age, gender, the number of additional disabilities, parental occupational skill level, ethnicity, parental hearing status, and academic achievement. Results: Data were received for 2241 children, 383 of whom had cochlear implants. Mean annual education cost ranged from &U20AC;15,745 for children with moderate hearing impairments to &U20AC;30,071 for nonimplanted children with profound hearing impairments and was &U20AC;28,058 for implanted children. A lower annual education cost was associated with a more favorable AHL, a later age at the onset of hearing impairment, female gender, a younger age, fewer additional disabilities, and a higher level of academic achievement. When these variables were controlled, costs were lower on average for implanted compared with nonimplanted children for the subset of children whose AHLs exceeded 111 dB. At the mean AHL of the implanted children (115 dB), implantation was associated with a reduction of &U20AC;3105 (95% confidence interval, &U20AC;1105 to &U20AC;5106) in annual education costs. Conclusions: Pediatric cochlear implantation is sufficiently effective to influence resource-allocation decisions in the education sector. The health-service cost of implantation is partly offset by savings in the cost of education. These savings occur without detriment to academic achievements.

Concordant Cues in Faces and Voices: Testing the Backup Signal Hypothesis

Information from faces and voices combines to provide multimodal signals about a person. Faces and voices may offer redundant, overlapping (backup signals), or complementary information (multiple messages). This article reports two experiments which investigated the extent to which faces and voices deliver concordant information about dimensions of fitness and quality. In Experiment 1, participants rated faces and voices on scales for masculinity/femininity, age, health, height, and weight. The results showed that people make similar judgments from faces and voices, with particularly strong correlations for masculinity/femininity, health, and height. If, as these results suggest, faces and voices constitute backup signals for various dimensions, it is hypothetically possible that people would be able to accurately match novel faces and voices for identity. However, previous investigations into novel face–voice matching offer contradictory results. In Experiment 2, participants saw a face and heard a voice and were required to decide whether the face and voice belonged to the same person. Matching accuracy was significantly above chance level, suggesting that judgments made independently from faces and voices are sufficiently similar that people can match the two. Both sets of results were analyzed using multilevel modeling and are interpreted as being consistent with the backup signal hypothesis.

Hearing-impaired children in the United Kingdom, III: cochlear implantation and the economic costs incurred by families.

Objectives: This article addresses two questions. First, are there differences in the economic costs incurred by families of hearing-impaired children depending on whether or not children have cochlear implants? Second, are these differences important when assessed from the perspective of society? Methods: In a cross-sectional survey, parents of a representative sample of hearing-impaired children provided data about annual resources used by the family because of their child’s hearing impairment. The data yielded estimates of two variables: out-of-pocket expenditure and time away from normal activities by parents. The economic cost of the two variables was estimated in &U20AC;uros (&U20AC;) at 2001/2 price levels, and summed to estimate the overall economic cost incurred by the family. Linear regression was used to estimate the association between costs and implantation, while controlling for average (unaided, preoperative) hearing level, age at onset of hearing impairment, age, gender, the number of additional disabilities, parental occupational skill level, ethnicity, and parental hearing status. The cumulative economic cost incurred by the families of implanted children, between implantation and age 16 yr, was calculated from estimates of the overall economic cost associated with implantation and compared with estimates of the incremental health-sector cost of implantation. Results: Data were provided by the families of 2858 children, 468 of whom had received a cochlear implant. Compared with the families of nonimplanted children, out-of-pocket expenditure was estimated to be significantly higher for families when children were implanted before the age of 5 yr and had used their implant for less than 2 yr, as was lost productivity when children had used their implants for less than 2 yr. Overall economic cost was estimated to be significantly higher for the families of implanted children who had used their implants for less than 2 yr. The cumulative economic cost was estimated to be &U20AC;3355 for a family whose child was implanted at age 3 yr and &U20AC;949 for a child implanted at age 6 yr. These costs correspond, at most, to 3% of the incremental health-sector costs of implantation. Conclusions: Compared with families of nonimplanted children, families of implanted children incur additional costs in the 2 yr after implantation. These costs are small in relation to the health-sector costs of providing implantation.

Matching novel face and voice identity using static and dynamic facial images

Research investigating whether faces and voices share common source identity information has offered contradictory results. Accurate face–voice matching is consistently above chance when the facial stimuli are dynamic, but not when the facial stimuli are static. We tested whether procedural differences might help to account for the previous inconsistencies. In Experiment 1, participants completed a sequential two-alternative forced choice matching task. They either heard a voice and then saw two faces or saw a face and then heard two voices. Face–voice matching was above chance when the facial stimuli were dynamic and articulating, but not when they were static. In Experiment 2, we tested whether matching was more accurate when faces and voices were presented simultaneously. The participants saw two face–voice combinations, presented one after the other. They had to decide which combination was the same identity. As in Experiment 1, only dynamic face–voice matching was above chance. In Experiment 3, participants heard a voice and then saw two static faces presented simultaneously. With this procedure, static face–voice matching was above chance. The overall results, analyzed using multilevel modeling, showed that voices and dynamic articulating faces, as well as voices and static faces, share concordant source identity information. It seems, therefore, that above-chance static face–voice matching is sensitive to the experimental procedure employed. In addition, the inconsistencies in previous research might depend on the specific stimulus sets used; our multilevel modeling analyses show that some people look and sound more similar than others.

Economic analysis and cochlear implantation

Abstract This review assesses the cost effectiveness of cochlear implantation (CI) for children and adults. Two arguments are offered: (i) an appropriate approach to estimating the cost effectiveness of CI is to use cost–utility analysis to estimate the cost of gaining a time-integrated unit of quality of life, expressed as a quality-adjusted life year (QALY). (ii) The Mark III Health Utilities Index is an appropriate self-report instrument for assessing the gain in quality of life associated with CI, provided that “quality of life” is interpreted as a measure of societys usual preference for better hearing rather than as an indication that impaired hearing equates to poor health. Cost–utility analysis shows that, for most groups of candidates, unilateral CI gains a QALY for significantly less than the value of €50,000 that has been inferred to define the upper limit of acceptability for the National Health Service in the United Kingdom (UK). Cost–utility ratios estimated for bilateral CI fall significantly above this limit, but could be acceptable in some countries that devote a higher percentage of their Gross Domestic Product to health care than the UK does at present.