Download Hearing loss is one of Australia`s most common forms of impairment

Hearing loss is one of Australia’s most common forms of impairment (Wilson et
al. 1999) yet it is considerably under diagnosed (Chung, Des Roches, Meunier, & Eavey,
2005). Though the gold standard for measuring hearing loss is a full audiological
examination, hearing loss can also be measured cheaply and efficiently with pen and
paper tests (see Coren, & Hakstian, 1992). The downside of the current questionnaires is
that they are only capable of detecting individual facets of hearing loss. Additionally, the
increased incidence of hearing loss amongst adolescents (see, Widén, Holmes, Johnson,
Bohlin, & Erlandsson 2009) has highlighted that hearing loss scales must be able to
capture potential future hearing loss. In response, the present study aimed to develop and
validate a simple questionnaire type test, which could be used not only to evaluate test
takers’ current hearing loss, but also take into account risk factors that would influence
NIHL in the future, identifying those that are at risk of developing NIHL, or further
damaging currently untreated NIHL. This may be of particular benefit to individuals who
may have a variety of psychosocial motives underlying their attitudes towards hearing
health issues (see Bohlin, Sorbring, Widén, & Erlandsson, 2011; Bohlin, & Erlandsson,
2007).
The sense of hearing is derived from converting mechanical pressure in the air to
nerve signals to the brain via hair like cilia in the inner ear. This begins with air pressure
entering the ear canal and arriving at the eardrum, from here the sound waves against the
ear drum are transduced through several bones in the middle ear where it then arrives at
the cochlea, the inner ear. Waves in the fluid of the inner ear stimulate cilia, hair shaped
cells which respond to different frequencies. This movement is passed to the auditory
nerve and to the brain, providing the sense of hearing. However, prolonged exposure to
loud noise damages the hair cells in the cochlea, such that they are no longer able to
effectively communicate information to the brain (Kalat, 2002).
Sound pressure level is measured in decibels (dB), this coefficient of sound
pressure level is a logarithmic scale, and each additional 20dB is a 10-fold increase in
sound pressure level (Goldstein, 2002). Damage to the hair cells in the inner ear is caused
by a combination of amplitude of sound pressure levels and the duration of exposure to
the noise (Kalat 2002). An increase in either of these factors will increase the damage to
hearing, in some cases leading to irreversible hearing loss where there is permanent death
of hair cells in the inner ear. For example, permanent hearing loss can occur following
use of a lawn mower (90dB approx) for two hours, however, being in a nightclub (>100
dB) can lead to permanent hearing damage in less than 15 minutes (values taken from
National Acoustic Laboratories, 1983). Moreover, the hair cells in the inner ear are
frequency specific, and as such, there is often loss of specific frequencies in hearing,
rather than a global deficit (National Acoustic Laboratories, no date). It is important to
realize that the volume and duration of exposure that can cause permanent damage is
below the physical pain threshold (REFERENCE) and as such there is no obvious
indicator to the sufferer that their hearing is being permanently damaged. Despite one’s
genuine concern of their general health and physical wellbeing, without the correct
knowledge or awareness of these contributing factors to NIHL, it would be difficult to
expect the proper preventive steps to be taken by anyone.
In terms of occupational hearing loss, Australian businesses and industry is held
to a high standard (see Safe Work Australia, 2004). This awareness and use of hearing
protection strategies is rigorously audited and enforced by governing bodies, ensuring
that employees are well cared for in their workplace. However, exposure to high noise
levels in non-professional environments such as home renovation, hunting, playing in a
musical group, automotive repair, use of petrol engine driven gardening tools and
spectating aviation, car and motorcycle events, can often be as damaging as occupational
exposure and are often done with no hearing protection (Daniel, 2007; Neitzal, Gershon,
McAlexander, Magda, & Pearson, 2012). In addition to this increase of harmful
recreational noise exposure, there are many who are unaware of the health risks
associated with these seemingly harmless activities (Danhauer et al., 2012). It appears
that there is a lack of knowledge regarding hearing health in the non-professional
industry. Additionally, young people who frequent concerts and night clubs may expose
themselves to dangerously high levels of noise, and perhaps more importantly, are less
likely to use hearing protection (Bogoch, House, & Kudla, 2005; Widén, et al., 2009).
Moreover, with the proliferation of personal media devices, opportunity for exposure has
increased dramatically and has become a primary source of noise exposure (Neitzal, et
al., 2012), particularly amongst young people (for review, see Vogel, Brug, Ploeg, &
Raat, 2007).
With greater opportunity for noise exposure, an important aspect of potential risk
for hearing loss is behaviours and attitudes towards hearing health (Vogel, et al., 2007).
An association has been drawn between risk taking behaviours, and an increased
likelihood of engaging in activities which are detrimental to hearing health in a
population of 15-20 year olds (Bohlin, and Erlandsson, 2007). Young people are apt to
expose themselves to high risk environments, and are also less likely to use hearing
protection (Widén, et al., 2009). Bohlin, and Erlandsson (2007) highlight that any
measure of hearing loss in a young population should take into account their attitudes
towards hearing loss and its social impact. It should be noted that a survey conducted by
Australian Hearing (2008) suggests that attitudes towards hearing loss and hearing
protection tend to increase in safety as one gets older, and as such it seems important to
take age into account when measuring the effect of attitude on hearing loss.
There is some degree of contention regarding the effect of education on exposure
to noise. Royster (1990, as cited in Crandell, et al., 2004) found that educational
programs specifically designed to increase knowledge about hearing loss were an
effective tool for inducing protective behaviour and mitigating noise exposure. Moreover,
Punch, Elfenbein, and James (2011) reiterate the importance of well targeted hearing loss
education programs in instigating protective behaviours, especially amongst adolescents.
Hence, it appears that any scale which claims to comprehensively measure hearing loss
must take into account the effects of education on noise exposure.
Whilst better education can be viewed as the bridge between the gap of NIHL and
preventive behaviours, Crandell, et al. (2004), found that a great proportion of their
sample were aware of hearing protection devices and their benefit, however, most of
them did not utilise these devices when necessary. It was suggested that socio-cultural
pressures to conform to the image of competence and stylistic norms were reasons that
encouraged such reckless behaviour (Crandell, et al., 2004). This finding is consistent
with findings from Bohlin, et al. (2011) who found that in a group of Swedish secondary
school students, knowledge of the potential harmful effects of noise exposure was quite
high, yet protective behaviour was quite low, suggesting that perhaps some age groups
may not view hearing loss to be serious, despite their knowledge of the matter. The
Protection Motivation Theory (PMT, Rogers, 1983, Rogers, & Prentice-Dunn, 1997)
stipulates that one’s propensity to perform adaptive behaviours (in this case hearing
protection) is dependent on the perception of the severity of the risks, and as the effects
of NIHL are gradual and not immediately obvious, the perceived benefits of social
competence or immediate gratification of loud music may outweigh the perceived
damage of dangerous noise levels. Thus, exposure to noise may occur irrespective of
domain specific knowledge.
Though the gold standard for detecting hearing loss is a full audiological
assessment, it requires more effort than a simple questionnaire which can be cheaply
administered by either a GP or self-report. Thus, a questionnaire may prove to have a
greater reach in terms of the general population. While it would be possible to produce
more exhaustive assessment of all factors which relate to exposure to noise and risk
activities, it was considered to be important to develop a test which could be easily scored
and accessed, and did not place undue time demands on those taking part. In the broader
context, this test should be of benefit to the Australian community through a larger
number people assessed for hearing loss, and a greater level of awareness of the
permanent nature of exposure related hearing loss. The test being simple to administer
and score may lead to more false positives than a more complex and longer test, but as it
is the intention to have all positive test results re-assessed by a full audiological exam, it
was deemed prudent, and in the best interests of all participants to allow this.
Subjective measures of existing hearing loss have been shown to be valid when
compared with objective audiometric assessment. Coren, and Hakstian (1992) developed
a 12 item scale which measures existing hearing loss. This scale was shown to have an
especially high level of validity in terms of its correlation with objective audiology
measurement (r = .81). And as such, the present scale takes into account the methodology
used in the HSI. Other scales which have investigated factors relating to hearing loss
include the Youth Attitudes to Noise Scale (YANS, Olsen, & Erlandsson, 2004), this
scale measured factors which contribute to how young people perceive hearing
protection, hearing health, and psychosocial factors.
However, as mentioned previously, existing hearing loss questionnaires do not
comprehensively measure both existing hearing loss, and risk factors relating to potential
hearing loss, and as such appear to be limited in their clinical relevance. Hence, with an
aim for clinical utility, the present study aimed to develop a scale which measures
existing hearing loss, and attitudes such as thrill seeking behaviour, and attitudes towards
hearing protection in the general Australian population. The primary justification of
validating a new scale is to comprehensively measure existing hearing loss, as well as
domain specific attitudes and education whilst controlling for social desirability factors
which may affect one’s willingness to report to hearing loss.
Punch, J. L., Elfenbein, J. L., & James, R. R. (2011), Targeting hearing health messages
for users of personal listening devices, American Journal of Audiology, 20, 69-82