Tag Archives: Hearing loss

Hearing screening for school children: Comparison of low-cost, computer-based and conventional audiometry

Resources

McPHERSON, B., Law, M.M.S. and Wong, M.S.M. Hearing screening for school children: Comparison of low-cost, computer-based and conventional audiometry. Child: care, health and development, 36, 323-331. 2010.
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2214.2010.01079.x/abstract

Abstract

Background:

There is a need to develop affordable but effective audiometric screening equipment, particularly for use in low-income countries. With advances in computer technology, low-cost computer-based audiometer software has been developed. However, the efficacy of computer-based audiometers in hearing screening and diagnostic assessment requires investigation. The purpose of this study was to evaluate the accuracy of a low-cost, computer-based audiometric system in a school-based hearing screening programme.

Methods:Eighty children were screened using the computer-based audiometer and with a conventional pure tone screening audiometer. Overall refer rates, as well as frequency and age effects on the accuracy of the computer-based audiometer, were considered.

Results:There was a significant relationship between the low-cost, computer-based audiometer and a conventional pure tone audiometer when a 40 dBHL refer criterion was used in school hearing screening and when test results at 500 Hz were excluded from analysis. However, background noise effects and software limitations in the computer-based system had major adverse effects on screening performance.

Conclusions:

The study results and preliminary practical experience with the system suggest that, with further software and hardware improvements, a low-cost, computer-based system may well be feasible for routine school screening in developing countries.

 

Hearing screening for school children: utility of noise-cancelling headphones

Lo, A.H.C. and McPHERSON, B. Hearing screening for school children: utility of noise-cancelling headphones. BMC Ear, Nose and Throat Disorders, 13:6. 2013.

Abstract

Background

Excessive ambient noise in school settings is a major concern for school hearing screening as it typically masks pure tone test stimuli (particularly 500 Hz and below). This results in false positive findings and subsequent unnecessary follow-up. With advances in technology, noise-cancelling headphones have been developed that reduce low frequency noise by superimposing an anti-phase signal onto the primary noise. This research study examined the utility of noise-cancelling headphone technology in a school hearing screening environment.

Methods

The present study compared the audiometric screening results obtained from two air-conduction transducers—Sennheiser PXC450 noise-cancelling circumaural headphones (NC headphones) and conventional TDH-39 supra-aural earphones. Pure-tone hearing screening results (500 Hz to 4000 Hz, at 30 dB HL and 25 dB HL) were obtained from 232 school children, aged 6 to 8 years, in four Hong Kong primary schools.

Results

Screening outcomes revealed significant differences in referral rates between TDH-39 earphones and NC headphones for both 30 dB HL and 25 dB HL criteria, regardless of the inclusion or exclusion of 500 Hz results. The kappa observed agreement (OA) showed that at both screening intensities, the transducers’ referral agreement value for the 500 Hz inclusion group was smaller than for the 500 Hz exclusion group. Individual frequency analysis showed that the two transducers screened similarly at 1000 Hz and 2000 Hz at 25 dB HL, as well as at both 30 dB HL and 25 dB HL screening levels for 4000 Hz. Statistically significant differences were found for 500 Hz at 30 dB HL and at 25 dB HL, and for 1000 Hz and 2000 Hz at 30 dB HL. OA for individual frequencies showed weaker intra-frequency agreement between the two transducers at 500 Hz at both intensity criterion levels than at higher frequencies.

Conclusions

NC headphones screening results differed from those obtained from TDH-39 earphones, with lower referral rates at 500 Hz, particularly at the 25 dB HL criterion level. Therefore, NC headphones may be able to operate at lower screening intensities and subsequently increase pure-tone screening test sensitivity, without compromising specificity. NC headphones show some promise as possible replacements for conventional earphones in school hearing screening programs.

Chinese speech audiometry material: Past, present, future

 Ma, X.,McPHERSON, B. and Ma, L. Chinese speech audiometry material: Past, present, future. Hearing, Balance and Communication, 11, 52-63. 2013

Speech audiometry plays an important role in the assessment of hearing abilities, as it may more accurately reflect auditory function in the daily communication environment of listeners than other auditory assessment measures. Speech perception tests have been developed for over a century in Western countries, and they are commonly used procedures in North America and Europe, as well as Australia. The course of history and scientific progress has influenced speech audiometry in both its clinical and research aspects. Test materials developed from syllables and words to phases and sentences, and test protocols have evolved from using only simple speech stimuli in quiet to hearing-in-noise tests. In the early years, the purpose of speech audiometry was primarily to evaluate telecommunication systems. Today, speech tests are more often applied to assess speech perception abilities for individuals with hearing impairment. In addition to aiding diagnosis of the location of peripheral auditory pathology and measuring (central) auditory processing abilities, with the development of auditory amplification devices speech tests are also utilized to assess the outcomes of hearing aid and cochlear implant rehabilitation. Compared to the well documented speech test materials of Western countries, development in this field in China has been relatively delayed. A lack of material standardization, few test versions for the numerous Chinese dialect groups or for non-Chinese language minority populations, and insufficient test materials for children, have obstructed the development of speech audiometry in China. This review highlights key research milestones in the development of Chinese speech audiometry material, including work conducted in mainland China, Hong Kong, and Taiwan, and suggests priorities for future research in this field in China.