Development of a Dutch matrix sentence test to assess speech intelligibility in noise.

OBJECTIVE: A Dutch matrix sentence test was developed and evaluated. A matrix test is a speech-in-noise test based on a closed speech corpus of sentences derived from words from fixed categories. An example is "Mark gives five large flowers." DESIGN: This report consists of the development of the speech test and a multi-center evaluation. STUDY SAMPLE: Forty-five normal-hearing participants. RESULTS: The developed matrix test has a speech reception threshold in stationary noise of - 8.4 dB with an inter-list standard deviation of 0.2 dB. The slope of the intelligibility function is 10.2 %/dB and this is slightly lower than that of similar tests in other languages (12.6 to 17.1 %/dB). CONCLUSIONS: The matrix test is now also available in Dutch and can be used in both Flanders and the Netherlands.

Hearing in adults with Pompe disease.

Hearing loss has been recognized as an important cause of morbidity in infants with Pompe disease, a metabolic disorder caused by deficiency of acid α-glucosidase. It is unknown whether hearing is also affected in adult Pompe patients. We have studied the prevalence, severity, and type of hearing loss in 58 adult patients using tympanometry and pure-tone audiometry. Compared to normative data (International Organisation for Standardisation standard 7029), 72% of patients had impaired hearing thresholds at one or more frequencies in at least one ear. All measured frequencies were equally affected. All patients had a sensorineural type of hearing loss, pointing to cochlear or retrocochlear pathology. Categorised according to the standards of the World Health Organisation 21% of patients had a clinically relevant hearing loss (16% slight, 3% moderate, 2% profound). Though this suggests that hearing loss occurs in a considerable number of patients with Pompe disease, this prevalence is similar to that in the general population. Therefore, we conclude that hearing loss is not a specific feature of Pompe disease in adults.

Estimating adolescent risk for hearing loss based on data from a large school-based survey.

OBJECTIVES: We estimated whether and to what extent a group of adolescents were at risk of developing permanent hearing loss as a result of voluntary exposure to high-volume music, and we assessed whether such exposure was associated with hearing-related symptoms. METHODS: In 2007, 1512 adolescents (aged 12-19 years) in Dutch secondary schools completed questionnaires about their music-listening behavior and whether they experienced hearing-related symptoms after listening to high-volume music. We used their self-reported data in conjunction with published average sound levels of music players, discotheques, and pop concerts to estimate their noise exposure, and we compared that exposure to our own "loosened" (i.e., less strict) version of current European safety standards for occupational noise exposure. RESULTS: About half of the adolescents exceeded safety standards for occupational noise exposure. About one third of the respondents exceeded safety standards solely as a result of listening to MP3 players. Hearing symptoms that occurred after using an MP3 player or going to a discotheque were associated with exposure to high-volume music. CONCLUSIONS: Adolescents often exceeded current occupational safety standards for noise exposure, highlighting the need for specific safety standards for leisure-time noise exposure.

A cognitive model of tinnitus and hyperacusis; a clinical tool for patient information, appeasement and assessment.

Tinnitus and hyperacusis are both aggravating audiological symptoms. Their underlying mechanisms are not fully understood, but the pathophysiology involves a central mechanism rather than a peripheral one. There is no curative treatment. A review of the available research on tinnitus and auditory processing was conducted to connect insights gained from different approaches to the subject; this resulted in the development of a holistic view of both conditions. In this view, the chronic course of the symptoms is pathological and attributed to a stress-related lack of habituation. This article adds to the literature on tinnitus and hyperacusis by presenting a schematic model of the cognitive mechanisms which can be used clinically in patient information sessions which are geared towards provide reassurance and encouraging the development of coping skills. In cooperation with the patient, the model can also help in the identification of underlying pathology. Future aims of study are suggested, elaborating on the role of tinnitus and hyperacusis in normal auditory processing and on the value of insight. Finally, parallels are drawn between tinnitus and positive symptom syndromes in neuropsychiatry and some of its modern visions on their treatment.

Adolescents and MP3 players: too many risks, too few precautions.

OBJECTIVE: The goal was to assess risky and protective listening behaviors of adolescent users of MP3 players and the association of these behaviors with demographic characteristics and frequency of use. METHODS: In 2007, 1687 adolescents (12-19 years of age) in 68 classes in 15 Dutch secondary schools were invited to complete questionnaires about their music-listening behaviors. RESULTS: . Ninety percent of participants reported listening to music through earphones on MP3 players; 32.8% were frequent users, 48.0% used high volume settings, and only 6.8% always or nearly always used a noise-limiter. Frequent users were >4 times more likely to listen to high-volume music than were infrequent users, and adolescents in practical prevocational schools were more than twice as likely to listen to high-volume music as were those attending preuniversity education. CONCLUSIONS: When using MP3 players, adolescents are very likely to engage in risky listening behaviors and are unlikely to seek protection. Frequent MP3 player use is an indicator of other risky listening behaviors, such as listening at high volumes and failing to use noise-limiters.

Self-reported disability and handicap after hearing-aid fitting and benefit of hearing aids: comparison of fitting procedures, degree of hearing loss, experience with hearing aids and uni- and bilateral fittings.

Self-reported outcome on hearing disability and handicap as well as overall health-related quality of life were measured after hearing-aid fitting in a large-scale clinical population. Fitting was performed according to two different procedures in a double-blind study design. We used a comparative procedure based on optimizing speech intelligibility scores and a strictly implemented fitting formula. Hearing disability and handicap were assessed with the hearing handicap and disability inventory and benefit of hearing aids with the abbreviated profile of hearing aid benefit. Effects on health-related quality of life and depression were assessed with the EuroQol-5D questionnaire and the geriatric depression scale. We found that hearing-aid fitting according to either procedure had a significantly positive effect on disability and handicap associated with hearing loss. This effect lasted for several months. Only the effect on disability persisted after 1-year of follow-up. Self-reported benefit from hearing aids was comparable for both fitting procedures. Unaided hearing disability was more pronounced in groups of participants with greater hearing loss, while the benefit of hearing aids was independent from the degree of hearing impairment. First-time hearing aid users reported greater benefit from their hearing aids. The added value from a bilateral hearing-aid fitting was not significant. Overall health-related quality of life and incidence of depression did not alter after hearing-aid fitting.

The design of a project to assess bilateral versus unilateral hearing aid fitting.

Binaural hearing provides advantages over monaural in several ways, particularly in difficult listening situations. For a person with bilateral hearing loss, the bilateral fitting of hearing aids thus seems like a natural choice. However, surprisingly few studies have been reported in which the additional benefit of bilateral versus unilateral hearing aid use has been investigated based on real-life experiences. Therefore, a project has been designed to address this issue and to find tools to identify people for whom the drawbacks would outweigh the advantages of bilateral fitting. A project following this design is likely to provide reliable evidence concerning differences in benefit between unilateral and bilateral fitting of hearing aids by evaluating correlations between entrance data and outcome measures and final preferences.

Combined sensory impairment (deaf-blindness) in five percent of adults with intellectual disabilities.

Our purpose in this cross-sectional study with 1,598 adult clients who had intellectual disabilities was to obtain valid prevalences of sensory impairments and to identify associations. The diagnoses were made through ophthalmologic and audiometric assessments, applying WHO/IASSID definitions. Re-weighted prevalences were 5.0% (95% CI 3.9- 6.2%) for the total adult population; 2.9% (1.9-4.1), less than 50 years; and 11.0% (7.9- 14.7), 50 years and over. Apart from being 50 years of age and over, p = .000, risk factors were more severe intellectual disability, p = .0001, and Down syndrome, p = .001. Results show that the risk of combined sensory impairment in this population is considerably increased compared with the general population. Part of the underlying conditions are treatable or can be rehabilitated. However, the complete diagnosis had been identified in only 12%.

How should hearing screening tests be offered?

This paper deals with the question of how the general public should be addressed when offering hearing screening. Postal-based questionnaires in the United Kingdom, Germany, and The Netherlands were sent to users of hearing devices, those that are in the process of obtaining one, or those that have indicated that they have special interest in hearing. Results of the survey indicated that respondents were enthusiastic about the idea of being able to carry out hearing self-screening tests via the internet, telephone, or questionnaires. A questionnaire as a method to screen on hearing was generally preferred above using the internet, which was preferred over using the telephone for the test. About 27% of the respondents indicated to use exclusively one method. Most respondents indicated that either method provided would be of interest (41%), 17% indicated not to be interested in conducting screening tests using the internet.

Comparison of speech intelligibility in quiet and in noise after hearing aid fitting according to a purely prescriptive and a comparative fitting procedure.

We compared two different types of hearing-aid fitting procedures in a double-blind randomized clinical study. Hearing aid fittings based on a purely prescriptive procedure (the NAL-RP formula) were compared to a comparative fitting procedure based on optimizing speech intelligibility scores. Main outcome measures were improvement of speech intelligibility scores in quiet and in noise. Data were related to the real-ear insertion responses that were measured after fitting. For analysis purposes subgroups were composed according to degree of hearing loss, characterized by unaided speech intelligibility in quiet, previous experience with hearing aids, unilateral or bilateral fittings and type of hearing aid. We found equal improvement of speech intelligibility in quiet, while fitting according to the prescriptive formula resulted in a somewhat better performance as expressed by the speech-to-noise ratio in comparison to the comparative procedure. Both procedures resulted in comparable real-ear insertion responses.

Comparative studies on hearing aid selection and fitting procedures: a review of the literature.

Although a large number of fitting procedures have been developed and are nowadays generally applied in modern hearing aid fitting technology, little is known about their effectiveness in comparison with each other. This paper argues the need for comparative validation studies on hearing aid fitting procedures based on the design of a randomized clinical trial and carried out in a large-scale clinical population. These studies are hard to conduct but can provide detailed information on the various aspects of the rehabilitation with hearing aids. The design of several recently reported comparative studies of hearing aid fitting procedures will be reviewed. This gives rise to a number of comments on aspects like, study design, composition of the study population and definition of outcome measures rather than on the outcome or conclusions of these studies themselves.

Choosing between measures: comparison of EQ-5D, HUI2 and HUI3 in persons with hearing complaints.

OBJECTIVES: To generate insight into the differences between utility measures EuroQol 5D (EQ-5D), Health Utilities Index Mark II (HUI2) and Mark III (HUI3) and their impact on the incremental cost-effectiveness ratio (ICER) for hearing aid fitting METHODS: Persons with hearing complaints completed EQ-5D, HUI2 and HUI3 at baseline and, when applicable, after hearing aid fitting. Practicality, construct validity, agreement, responsiveness and impact on the ICER were examined. RESULTS: All measures had high completion rates. HUI3 was capable of discriminating between clinically distinctive groups. Utility scores (n = 315) for EQ-5D UK and Dutch tariff (0.83; 0.86), HUI2 (0.77) and HUI3 (0.61) were significantly different, agreement was low to moderate. Change after hearing aid fitting (n = 70) for HUI2 (0.07) and HUI3 (0.12) was statistically significant, unlike the EQ-5D UK (0.01) and Dutch (0.00) tariff. ICERs varied from 647,209 euros/QALY for the EQ-5D Dutch tariff to 15,811 euros/QALY for HUI3. CONCLUSION: Utility scores, utility gain and ICERs heavily depend on the measure that is used to elicit them. This study indicates HUI3 as the instrument of first choice when measuring utility in a population with hearing complaints, but emphasizes the importance of a clear notion of what constitutes utility with regard to economic analyses.

Potential barriers and facilitators for implementation of an integrated care pathway for hearing-impaired persons: an exploratory survey among patients and professionals.

BACKGROUND: Because of the increasing costs and anticipated shortage of Ear Nose and Throat (ENT) specialists in the care for hearing-impaired persons, an integrated care pathway that includes direct hearing aid provision was developed. While this direct pathway is still under investigation, in a survey we examined expectations and potential barriers and facilitators towards this direct pathway, of patients and professionals involved in the pathway. METHODS: Two study populations were assessed: members of the health professions involved in the care pathway for hearing-impaired persons (general practitioners (GPs), hearing aid dispensers, ENT-specialists and clinical audiologists) and persons with hearing complaints. We developed a comprehensive semi-structured questionnaire for the professionals, regarding expectations, barriers, facilitators and conditions for implementation. We developed two questionnaires for persons with hearing complaints, both regarding evaluations and preferences, and administered them after they had experienced two key elements of the direct pathway: the triage and the hearing aid fitting. RESULTS: On average GPs and hearing aid dispensers had positive expectations towards the direct pathway, while ENT-specialists and clinical audiologists had negative expectations. Professionals stated both barriers and facilitators towards the direct pathway. Most professionals either supported implementation of the direct pathway, provided that a number of conditions were satisfied, or did not support implementation, unless roughly the same conditions were satisfied. Professionals generally agreed on which conditions need to be satisfied. Persons with hearing complaints evaluated the present referral pathway and the new direct pathway equally. Many, especially older, participants stated however that they would still visit the GP and ENT-specialist, even when this would not be necessary for reimbursement of the hearing aid, and found it important that the ENT-specialist or Audiological Centre evaluated their hearing aid. CONCLUSION: This study identified professional concerns about the direct pathway for hearing-impaired persons. Gaps exist in expectations amongst professions. Also gaps exist between users of the pathway, especially between age groups and regions. Professionals are united in the conditions that need to be fulfilled for a successful implementation of the direct pathway. Implementation on a regional level is recommended to best satisfy these conditions.

Prevalence of hearing loss in 1598 adults with an intellectual disability: cross-sectional population based study.

A cross-sectional epidemiological study on prevalence of hearing loss was carried out in an age- and Down's syndrome- stratified random sample of 1598 persons drawn from a base population of 9012 persons, representative of the Dutch adult population of intellectual disability (ID) service users. The re-weighted population prevalence is 30.3% (95% confidence interval [CI]: 27.7-33.0%). Subgroup prevalences range from 7.5% (95% confidence interval [CI]: 3.6-13.3) in the subgroup aged 18-30 years with ID by other causes than Down's syndrome, up to 100% (95% CI: 79.4-100%) in adults over 60 years of age with Down's syndrome. Down's syndrome (OR 5.18, 95% CI 3.80-7.07) and age were confirmed to be risk factors. Age-related increase in prevalence in persons with Down's syndrome appears to occur approximately three decades earlier, and in persons with ID by other causes approximately one decade earlier than in the general population.

Effects of high-frequency emphasis and compression time constants on speech intelligibility in noise.

The objectives of the study were to evaluate the effect of different settings with regard to speech intelligibility in noise both objectively and subjectively and thus determine a favoured setting of compression time parameters, pre-set program (high-frequency emphasis) or combination for each individual user in a prospective study. Another objective was to evaluate the relationship between patient characteristics (e.g. slope of hearing loss) and favoured settings. In total, 38 subjects divided over five audiological centres were fitted with the Philips Spaceline D71-40 BTE digital hearing aid. Subjects were asked to compare three predefined compression algorithms with different time constants, slow (indicated by the manufacturer as AVC), intermediate (NORMAL) and fast (SYLLABIC) over two 4-week periods using the intermediate setting in both comparisons and randomizing over the fast and slow conditions. A randomization determined whether a subject started with the comfort-oriented pre-set program (AUTO) or the speech intelligibility-oriented setting with high-frequency emphasis (SPIN). In a third 4-week period, the pre-sets AUTO and SPIN were compared using the setting of the compression time constants that gave the best results during the first two periods. Comparisons were made using a standard speech-in-noise test with three types of noise: continuous speaker noise, modulated ICRA-4 noise, and car noise. The patients were also asked to fill in a Dutch translation and adaptation of the APHAB questionnaire to indicate their impression of performance. The results indicate that no compression algorithm, pre-set or combination is favoured overall. The largest improvement in speech-in-noise scores was found with syllabic compression. The advantageous effect of high-frequency emphasis after optimization of compression timing is small. The APHAB showed that users tend to prefer the SPIN setting. We found no relationship between favoured compression or pre-set and the degree or steepness of the hearing loss User preference and best performance in noise do not always coincide. Acclimatization may play a role. It could be advisable to let a user listen to a subjectively less favoured condition for at least some time if an optimal setting for speech intelligibility in noise is preferred over comfort.

The effects of phonemic compression and anti-upward-spread-of-masking (anti-USOM) on the perception of articulatory features in hearing-impaired listeners.

The effect of speech processing on articulatory-feature recognition was studied in a group of hearing-impaired listeners with high-frequency sensorineural losses. Individual difference scaling (INDSCAL) and sequential information analysis (SINFA) were applied to a set of consonant-vowel-consonant responses measured under various conditions of speech processing. The processing consisted of high-frequency phonemic compression combined with compensation for anti-upward-spread-of-masking (i.e. anti-USOM). In quiet, we found an improved recognition of frication with compression, whereas additional anti-USOM improved the recognition of the second and third vowel-formants. In background noise, we found remarkably negative effects of anti-USOM on the recognition of features containing low-frequency cues, such as voicing and nasality. We conclude that the combined results of SINFA and INDSCAL provide important insights into the possibilities and limitations of phonemic compression and anti-USOM.