Voice changes occurring with ageing in the absence of disease are often referred to as presbyphonia. Despite attempts to describe this phenomenon, there is no established acoustic and perceptual profile of voice in healthy ageing populations. Diverse acoustic software programs have been used to acoustically describe older voices; however, the differences of acoustic measure outcomes make it difficult to clearly profile older voices. This thesis seeks to review our current understanding of acoustic and perceptual changes in voice across sex and age. It also generates novel data on these features in healthy adults over 50 years alongside measures of quality of life. One hundred and fifty one healthy adults over 50 years old were analysed with three different acoustic programs (48 acoustic measures), an auditory-perceptual voice assessment and voice-related quality of life questionnaire. Roughness, breathiness and tremor were key perceptual features identified in the cohort. Deviant acoustic features that varied across age included amplitude perturbation, frequency perturbation, spectral noise, tremor and cepstral/spectral parameters. Age was best predicted using a multiparameter feature metric (including amplitude perturbation, spectral noise and cepstral/spectral parameters). Acoustic and perceptual features correlated. There was some evidence that voice related quality of life is affected in healthy older adults. Vocal fold physiology and biomechanics were not investigated in this study, however clear differences in voice quality were observed in older age groups. These changes may be explained by biomechanical or structural changes to systems important for voice production including resonance, respiratory and vocal fold movement. We have brought together the disparate literature in this field and systematically investigated acoustic and perceptual features of voice in healthy older adults. These data provide a foundation on which to further explore the underlying mechanisms for change and establish a series of norms for current listener and objective studies into voice of adults with and without disease.

Thesis abstract Background: Previous studies suggest person-centred care (PCC) might improve adult hearing rehabilitation uptake and use. Despite this, PCC has not been widely implemented within hearing rehabilitation organisations (HROs) in Australia. To date, research has not focused on the criteria used by senior managers, who are ultimately responsible for decisions on implementation of clinical practice within their HRO, to evaluate outcomes of providing PCC or its impact on organisational success. Better understanding of these criteria may be relevant to understanding the current low uptake of PCC in clinical practice and how this might be increased. Aims: To investigate how senior managers of HROs in Australia define and evaluate: i) success; and ii) PCC; and iii) to identify their perceived facilitators of and barriers to PCC evaluation. Following these, iv) to evaluate the organisational-valued outcomes of a person-centred intervention delivered to graduate intern audiologists. Design: We used a pragmatic, exploratory sequential mixed-methods design. In the qualitative first phase, we conducted semi-structured interviews with sixteen senior managers from twelve HROs across Australia. For the quantitative second phase, a non-randomised cohort comparison trial was conducted within a large HRO between two groups of interns and their clients. Intervention group interns received training and support to use psychosocial communication with their clients in addition to the standard training received by control group interns. Organisational-valued client, clinician and financial outcomes were identified from the first phase. Sixteen intervention and eleven control group interns completed surveys three months after commencing their internships. Clients (intervention n = 235, control n = 181) seen in the following three months had their appointment details analysed and received postal surveys two months after their initial appointment. Results: In phase one, senior managers defined success as the crucial interplay of client success and financial success. This interaction was influenced by staff factors, the organisation’s ethos and the senior manager’s role. Financial success was evaluated more rigorously than client success, with client success assessed primarily in clients who adopted hearing aids. PCC was defined well but not evaluated by senior managers due to beliefs that their clinicians and clinical processes were effective in providing PCC based on existing client and financial successes. In phase two, intervention group interns reported significantly greater intention to stay with the organisation. Intervention group clients adhered significantly more to clinician recommendations of hearing aids and reported greater benefit with hearing aids in social situations. Control group clients were significantly more likely to recommend hearing aids and the clinic to friends and family. PCC evaluation measures did not reveal significant overall differences between groups. Non-significant results may be clinically relevant as device technology levels and uptake were higher for the intervention group for fewer total appointments. Implications Senior managers of HROs valued PCC in success but did directly evaluate it. Clinically validated PCC evaluation tools are still needed. The psychosocial communication intervention was associated with benefits to the HRO that were valued by senior managers, but further investigation is warranted to assist the uptake of PCC in HROs.

INTRODUCTION: Previous research has identified a relationship between hearing loss and cognitive impairment/dementia in older adults, however this research has primarily focused on measures of sensorineural hearing loss (SNHL). Central Auditory Processing (CAP), an ability which decreases with increasing age, is recognised as important for understanding speech in background noise, but is not routinely considered in audiological assessment or hearing-cognition research. Yet, some studies have provided evidence that poorer performance on some measures of CAP ability significantly relate to reduced cognitive function and/or increased likelihood of dementia diagnosis. Although there is no known treatment for cognitive impairment, hearing impairment is to some extent treatable with hearing aids (HAs). OBJECTIVES: This study aimed to examine the relationship between hearing impairment and cognitive impairment by assessing both peripheral hearing loss and CAP ability. Additionally, this research aimed to investigate how hearing, cognition and personal factors influence HA outcomes (uptake/use/benefit) in older adults. DESIGN: Experimental study design with 85 older adults between the ages of 60.33 and 80.08 (m =70.23, SD = 5.17). SNHL was assessed using Pure Tone Audiometry (PTA), the Listening in Spatialised noise-Sentences (LiSN-S) test and Dichotic Digits Test. Cognition was measured using the Cogstate Brief Battery. Personal factors were recorded from participant’s answers on a series of take-home questionnaires. Hearing aid benefit and use was subjectively reported at three- and six-months post HA fitting. RESULTS: Results for three of the four LiSN-S conditions shared a significant correlation with at least one cognitive measure, and SNHL was also significantly related to two cognitive domains (attention and executive function) in this cohort. Those who decided to use HAs had significantly poorer hearing as measured by both PTA and the LiSN-S test, and those with poorer hearing reported greater HA benefit. Lastly, stronger psychomotor function was associated with greater reported use of HAs at three- and six-months post HA fitting. Greater family interaction and attention scores also were associated with greater HA use at three- and six-months post fitting respectively. IMPLICATIONS: The older hearing-impaired patient may present with a combination of hearing loss, decreased auditory processing ability and impaired cognitive ability. It may be prudent to consider the presence and possible interactions of multiple health conditions as well as psychosocial factors when determining the appropriate management pathway for and expectations of the patient. Future research should investigate longitudinal cognitive implications for patients presenting with a SP deficit. Also, for older adults presenting with a SP deficit, the benefits of early referral for cognitive assessment should be considered. Moreover, a combination of hearing, cognitive and psychosocial factors impact HA outcomes in older Australians. These factors should be considered in audiological rehabilitation to best maximise patient HA outcomes, and further research should consider the long-term clinical implications HA fitting has on natural cognitive decline in the elderly.

‘Auditory neuropathy’ is a nosological term coined by Starr et al. (1996) used to describe a group of hearing disorders, which are characterised by abnormal auditory nerve activity in the presence of normal cochlear outer hair cell function. While our understanding of this condition has advanced significantly since it was first identified almost 30 years ago, limitations in current diagnostic assessments make it difficult for clinicians to determine both the site(s) of lesion and the extent of dysfunction in an affected individual. As such, determining the most appropriate management strategy can be difficult. This is particularly salient for cochlear implantation, which is currently the intervention strategy of choice for individuals with auditory neuropathy. Cochlear implant outcomes, however, vary considerably and the inconsistency in post-operative speech perception ability is thought to be directly dependent on both the site(s) of lesion and extent of dysfunction. In this thesis, advanced diffusion MRI techniques were used to investigate changes in the white matter fibres of the VIII nerve and auditory brainstem in individuals with different forms of auditory neuropathy. Three major research questions formed the basis of this thesis and subsequently the three studies contained herein: (1) Can dMRI-based tractography techniques be used to reconstruct the pathways of the auditory brainstem in-vivo using clinically accessible MRI field strengths?; (2) Can newly developed dMRI-based quantitative analysis techniques be used to elucidate neurodegenerative changes within the brainstem of a genetically defined group of individuals with X-linked auditory neuropathy?; (3) Can these techniques be used to further our understanding of the underlying lesion site(s) and extent of neural dysfunction in a group of individuals with auditory neuropathy due to different aetiologies? The first study investigated the use of different diffusion models and tractography algorithms. Using these techniques, the pathways between the left VIII nerve and bilateral inferior colliculi were mapped in three normal hearing control subjects. Furthermore, the accuracy of tract reconstructions was compared between two different diffusion models: (i) the classic diffusion tensor model, and (ii) a high-order diffusion model called Single-Shell 3-Tissue constrained spherical deconvolution. Finally, the benefits of using the Anatomically-Constrained Tractography algorithm were also examined. To address question two, the second study used a novel dMRI-based quantitative analysis measure called Apparent Fibre Density as obtained from Single-Shell 3-Tissue Constrained Spherical Deconvolution and analysed with the fixel-based analysis framework to investigate white matter fibre-specific degeneration in a genetically characterised group of individuals with X-linked auditory neuropathy. This case-control study showed that individuals with X-linked auditory neuropathy had axonal degeneration throughout the auditory pathways, with the most significant degeneration being localised to the VIII nerve region. The results were supported by several objective auditory measures, which showed normal cochlear sensory function but significantly disrupted auditory nerve activity. Moreover, the results showed that the degree of temporal processing deficit was related to the severity of axonal degeneration in individuals with X-linked auditory neuropathy. Behavioural auditory assessments of sound detection, speech perception, and the processing of binaural cues were also significantly poorer in affected individuals compared to the normal hearing controls. Finally, the third study of this thesis used similar techniques to the second study, this experiment examined axonal degeneration in the VIII nerve region of individuals with auditory neuropathy from various aetiologies. Results were compared against participants with normal hearing. The Apparent Fibre Density findings showed that the auditory neuropathy group had significantly fewer auditory nerve fibres compared to controls. Overall, the Apparent Fibre Density metric was significantly correlated with auditory measures including, sound detection thresholds, speech perception and temporal processing ability, auditory brainstem response amplitudes, and binaural processing ability. Furthermore, the degree of axonal degeneration observed in each affected individual was consistent with the other available data, including clinical information, such as disease progression/duration of disease, and the known/assumed pathophysiological mechanism(s) underlying the auditory neuropathy phenotype. The results of this thesis offer insights into the site of lesion(s) and pathophysiological process underlying the auditory neuropathy phenotype. Furthermore, the findings provide evidence for the ability of advanced diffusion MRI techniques to be used as a diagnostic tool to examine the auditory subcortical white matter pathways in-vivo. Hence this technique may prove to be a useful adjunct to existing auditory assessments, which may in the future guide rehabilitation options for individuals with auditory neuropathy. Importantly, these techniques may be applied to related conditions where VIII nerve axonal density may affect patient outcomes, including managing cochlear or brainstem implant candidacy.

All children make errors as they learn to talk, and while the vast majority of children spontaneously attain error-free speech within a predictable timeframe, approximately 6% to 10% of children struggle to achieve intelligible speech without intervention for no apparent anatomical, physiological, or psychological reason (American Psychiatric Association, 2013). While much is now known about the types of speech sound errors these young children make (McLeod & Baker, 2017), little is known about why they make these errors. One explanation for these errors is that some children fail to deduce the correct rules governing how speech sounds combine legally to form words. This PhD thesis investigates the cognitive–linguistic profile of two widely recognised subgroups of children with speech sound disorders (SSD) of unknown origin: phonological delay, that is, children who make typical speech errors but are delayed based on the norms for their chronological age, and phonological disorder, that is, children who make atypical speech errors that are heard in less than 10% of children at any age. Over a series of five empirical studies, three core executive function processes were investigated in the same cohort of monolingual English-speaking preschool children with phonological delay, phonological disorder, and typically developing speech. Children were tested on a series of standardised and commonly employed receptive vocabulary, phonological short-term memory and phonological working memory tasks, inhibitory control tasks, and rule abstraction and cognitive (set) shift tasks. Results indicated that children with phonological delay and phonological disorder had separate and distinct cognitive–linguistic profiles. Specifically, children with phonological disorder had phonological short-term memory skills (i.e., ability to mentally ‘hold’ verbal information briefly) similar to children with typical speech development, while children with phonological delay did not. Further, both SSD subgroups demonstrated significantly reduced phonological working memory performance (i.e., ability to mentally ‘hold’ and ‘manipulate’ verbal information) compared to children with typical speech development. However, for children with phonological delay, phonological working memory was capped by their ‘holding’ performance rather than a specific difficulty mentally ‘manipulating’ verbal information, while children with phonological disorder (who have intact ‘holding’ performance) had specific difficulties mentally ‘manipulating’ verbal information. Finally, children with phonological disorder also demonstrated significant domain-general rule abstraction and cognitive (set) shift deficits compared to their peers with typical speech development and phonological delay. All children had receptive vocabularies within the typical range. These findings have both clinical relevance and implications for theories of typical and impaired phonological development. Specifically, the findings highlight (1) the importance of differential diagnosis and recognising SSD subgroups in SSD research and clinical practice, (2) the importance of understanding the role of both domain-general cognitive processes and linguistic processes to phonological acquisition and explaining SSD subtypes, (3) how and why deficits in rule abstraction and cognitive (set) shift may contribute to atypical phonological development and atypical speech errors, and (4) the need for third-generation intervention approaches, that is, innovative and tailored treatment techniques that concurrently address speech and literacy difficulties by targeting underlying deficits.

Sound levels in the live music industry have been demonstrated to reach levels capable of causing harm to the auditory system. The body of work presented here aimed to explore ways in which hearing injury can be prevented in the Australian music industry. To do so, multiple stakeholders were engaged, including venue owners, live-music sound engineers, audiologists and manufacturers of hearing protectors for musicians. Four discrete, mixed-methodology studies were conducted to address the topic. Study 1 aimed to investigate the clinical provision of musicians’ hearing protectors (MHPs) by audiologists and manufacturers of MHPs in Australia. Method. Audiologists and manufacturers were asked to complete one of two surveys, investigating the delivery of clinical care for musicians, and recommended processes relating to the manufacture of earplugs. Results. Inconsistencies in the clinical procedures were noted in both the practice of audiological care for musicians, and the recommendations made by manufacturers of MHPs. Study 2 aimed to investigate whether the use of, and satisfaction with, MHPs is influenced by the specific treatment delivered to musicians by audiologists. Method. Musicians rated their satisfaction with the services as delivered across the four treatment conditions. Results. No statistically significant differences across conditions were observed, however, certain aspects of care were perceived positively by musicians, such as the provision of a hearing test. Study 3 aimed to assess the hearing of live music sound engineers and their risk of hearing injury. Method. Participants completed a questionnaire on their hearing health as well as a hearing assessment. Results. Ninety-six percent of sound engineers reported having experienced at least one symptom of hearing injury during or after a work shift in music. Use of hearing protection was low, however, individuals who frequently wore hearing protection had significantly better hearing, particularly in the extended high frequencies. Study 4 aimed to investigate if the use of sound level management software can assist in reducing exposure levels in indoor live music venues. Method. Use of a commercial sound level management system in six indoor live-music venues of Melbourne was trialled. Results. Overall, there was no reduction in mean sound level (LAeq,T), however the number of nights on which extreme volume levels were recorded was reduced. Subjective questionnaires indicated that one-fifth of patrons would prefer lower sound levels than experienced. Overall, the results indicate there is a significant risk of hearing injury to individuals working within and attending live music venues in Australia. Findings indicated that there is a need for greater hearing awareness across all stakeholders. Audiologists would benefit from the development of best-practice guidelines for the care of musicians’ ears, while more broadly, the inclusion of EHF hearing thresholds would benefit in early detection and monitoring of noise-induced hearing loss. Greater research focus and hearing conservation training is needed for both LMSEs and staff in live-music venues, who would benefit from the implementation of strategies to manage venue sound levels in a way that takes into account the sound level preferences of patrons, while minimising the risk of hearing injury for all.

Speech therapy is a new and rapidly growing profession in Vietnam, yet factors shaping its development are not well understood. Previous research in Majority World contexts suggests the emergence of rehabilitation professions may be shaped by a set of shared factors; however, the utility of this information to the Vietnamese context is not known. Further, little is known of the experience of practising a profession embedded with Eurocentric notions of health and disability in different cultural contexts. This doctoral research sought to extend understanding of these issues by exploring how the speech therapy profession is emerging in Vietnam through the experiences of a group of Vietnam’s first speech therapy graduates. This research reports a longitudinal, qualitative study employing participatory research methods conducted across the different cultural settings of Australia and Vietnam. Phase 1 of the research was conducted between 2013 and 2014. In 2013, interviews with 13 of the Vietnamese graduates one year following their graduation supported the development of a model conceptualising their work. In 2014, eight of the graduates were interviewed about their professional practice at two years post graduation. An advisory group of the graduates was also convened at this time to guide the research over its duration. This research phase confirmed the utility of the conceptual model characterising the graduates’ work and drew focus to the complexities that may arise when conducting participatory research in a cross-cultural setting. In Phase 2 of the research, creative research methods were introduced to explore the graduates’ work at three years post graduation. This research phase led to refinement and elaboration of the model conceptualising the graduates’ professional practice. In the final research phase, participants reflected upon their professional journeys in the four years since graduating and upon their participation in the research. This research identified that a diversity of factors is shaping the emergence of the speech therapy profession in Vietnam. Some factors are shared with other countries of the Majority World where the profession is practised; some are unique to Vietnam. Key themes conceptualising the graduates’ work—scope of practice, developing identity, confidence to practise, progressing the profession, and feelings—provide a rich, nuanced understanding of their experiences. This study revealed that the experience of pioneering a new profession in a Majority World context will be shaped by structural, personal, interpersonal, and cultural factors, and that initiatives to introduce the speech therapy profession into novel contexts will best be informed by local practitioners. Learnings from doing participatory research in a cross-cultural context relate to the integral role of the interpreter and engaging in research when the researcher and research participants are separated by language, time, and distance. The use of creative research methods supported the research participants’ experiences to be represented in diverse ways and addressed challenges posed by translation and the potential for misrepresentation of their experiences. This research highlighted that the experience of participating in research will be shaped by personal motivations and learnings that arise from research.

Early auditory exposure and linguistic interactions are fundamental in shaping the trajectory of typical language development in hearing children. These early linguistic experiences occur within the context of adult-child exchanges, through daily experiences, care routines and play. For children with prelingual hearing loss, early access to sound through hearing devices enables them to participate in these early linguistic experiences and can mitigate the potential negative effects resulting from hearing loss. In addition to early device fitting, research has demonstrated a strong association between the manner, content and amount of spoken language which infants and toddlers are exposed to at home, to enhance their learning, and their later language outcomes. While there is growing research awareness with regard to measuring the amount of talk directed to children, establishing how best to provide feedback to caregivers on their language contributions to their children in the context of everyday life, has been a challenge in traditional service delivery models. To this end, automated speech and language processing technology, also known as the Language ENvironment Analysis (LENA) system, offers clinicians the possibility of measuring and imparting quantified information to parents about their child’s auditory-language environment. Additionally, the use of mobile applications has been gaining traction as an accessible method of promoting health. The Daily Vroom App (DVA) for example, was created as an outreach initiative to communicate developmental research evidence to parents, presented as practical and implementable content. The DVA content takes the form of daily tips aimed at turning everyday moments for parents and their young children into opportunities for shared interaction. This study evaluated these two technology-driven interventions, using LENA technology and the Daily Vroom App, as ways to increase the amount of conversational turns and words spoken by adults to children. The present study firstly investigated relationships between family, maternal and child characteristics and language counts (measured using the LENA system) recorded in the children’s natural home environments. Secondly, changes in the participants’ adult word count and adult-child conversational turn count from baseline were examined after mothers received feedback based on LENA generated language estimates and/or, after mothers had used the Daily Vroom App. Thirdly, survey findings regarding the use of LENA technology and the DVA from the perspective of clinicians and mothers were explored. There were 10 mother-child dyads (six hearing children and four children with bilateral severe-to-profound hearing loss) who participated in a prospective intervention trial. After establishing each dyad’s baseline LENA-generated language counts (adult words and adult-child conversational turns), mean percentage changes in their language counts were analysed for three study conditions: LENA-Only recordings of adult-child verbal interactions in the child’s natural environments (Condition LO); adult-child verbal interactions following specific, individualised feedback from a clinician regarding the quantity of talk (LENA Feedback- Condition LF); and DVA use which provided tips for shared parent-child interactions in addition to Condition LF (LENA Feedback and App- Condition LFA). Maternal and child measures were administered at the beginning of the study. Demographic information and responses to a survey on the use of LENA and mobile technology were collected from participating clinicians and mothers. Key group findings suggested that the mean percentage increases in adult word and conversational turn counts from baseline were significant after the interventions (i.e. providing participants with LENA feedback and mother’s use of the mobile app), compared to Condition LO where only LENA recordings were completed. Significant correlations were found between mothers’ occupational skill level, maternal receptive vocabulary and their ratings of eHealth literacy. Participants assigned the DVA an overall mean quality rating of 3.85 out of 5. Significant positive relationships were found between objective app quality indicators (engagement, aesthetics, information) and participants’ perceived impact (on help-seeking, intention to change and behaviour change) of using the DVA. These two contemporary technologies (LENA and DVA) were demonstrated to support adult language input and conversational turns in the home environments for mothers of children with normal hearing, and children with bilateral significant hearing loss. This study addressed the question of whether providing structured information and feedback to mothers would be associated with a change in maternal language behaviours. This study also contributed to current knowledge regarding the practical applications of the LENA system and the Daily Vroom App as a complement to current service models, extending intervention practices beyond the therapy room.

Vestibular migraine (VM) is one of the most common causes of recurrent vertigo with significant effects on patients’ health-related quality of life measures and psychological well-being. It is widely accepted that VM is associated with a range of diagnostic and management challenges for practitioners, predominantly due to the lack of a gold standard diagnostic test and absence of a preferred drug of choice. Consequently, the existing literature is mostly focused on optimising the diagnostics and treatment protocols. Yet, little is known about the therapeutic needs of those who suffer from VM and health professionals’ strategies in providing care beyond medication. This doctoral thesis addresses these gaps in knowledge in two ways: first, by exploring the experiences of vestibular migraineurs in their daily lives and in the management of their condition; second, by juxtaposing these experiences with an exploration of vestibular specialists’ (VSs) perspectives on the management and care of people with VM. This thesis entailed three phases. In Phase A, a preliminary observation of several vestibular migraineurs’ appointments with VSs was conducted to inform the overall direction of the thesis and to fine-tune the research questions. Phase B adopted a qualitative descriptive method across two consecutive studies. In Study 1, 11 adults with VM were interviewed. This study was informed by the preliminary observation in Phase A and explored two aims: 1a) vestibular migraineurs’ lived experiences and therapeutic needs, 1b) vestibular migraineurs’ experiences with healthcare professionals (HCPs). The findings are visually presented in two models: The first model describes participants’ perceptions of living with VM. In this model, VM is depicted as a ‘wall’ to represent participants’ perception of living with extensive functional and psychosocial restrictions. The individual is presented at the centre, surrounded by six aspects of life (i.e., lifestyle, occupation, personal life, self-sufficiency, social network and self-image) and encircled by VM. Hopelessness and isolation are presented adjacent to the VM ‘wall’ to highlight the psychological effects of a restricted life. The second model is a map of vestibular migraineurs’ journeys from symptom presentation to diagnosis/symptom control. This map illustrates the experiences of vestibular migraineurs with different HCPs and represents the convoluted, long and often frustrating journey that patients embark on to find a diagnosis and, possibly, some level of symptom control. This model shows that vestibular migraineurs’ journeys often entail multiple misdiagnoses, dismissals and irrelevant referrals, particularly when patients seek medical advice from general practitioners (GPs). This experience often leads to frustration and loss of trust towards primary care physicians. By contrast, participants depicted a more positive, trusting experience when seeing VSs. Compared to GPs, patients often perceived VSs as more knowledgeable and competent in managing their illness, largely because VSs acknowledged the severity of their illness and did not dismiss them. Vestibular migraineurs’ satisfaction with VSs provided a rationale for exploring these practitioners’ perspectives. The purpose was to elucidate the source of patients’ higher levels of satisfaction and to explore the clinical strategies that VSs adopted in managing VM. Study 2 explored the perspectives of 10 VSs on two topics: 2a) the complexities of VM management and 2b) the features of optimum VM care. VSs were recruited from several fields of balance disorder management including neuro-otology, vestibular audiology, vestibular physiotherapy, and ear, nose and throat surgeons. The outcomes are depicted in two models. The first model illustrates the multidimensionality of complexities posed by VM, indicating that VM is a complex illness to manage due to three factors: 1) scientific ambiguities, 2) patient-related challenges and 3) professional challenges. The second model proposes a framework for VM quality management: ‘SAIPHE’. SAIPHE stands for the six elements that were considered essential for VM quality care: self-efficacy, access, individualisation, wholistic, and education. Each of these elements are described in detail in the thesis. Study 2 concludes Phase B of this thesis. In Phase C, the data obtained in this body of work was triangulated. The outcomes of Study 1 and Study 2 were juxtaposed to examine their consistency. Patients’ accounts of the challenges of living with VM were compared with VSs’ perspectives and elements of SAIPHE were juxtaposed with Study 1 (vestibular migraineurs’ lived experience and expectations of their practitioners). Finally, VSs’ perspectives on features of VM patients’ education/consultation were integrated with vestibular migraineurs’ articulated educational needs and were developed into a VM-specific consultation framework. Overall, the outcomes of this thesis indicate that VM is a complex illness to live with and to manage as its effects extend beyond its immediate symptoms. Patients suffer from functional and psychological implications that, if unattended, could have catastrophic sequelae. Despite advances in evidence-based knowledge, and despite the consistency of VSs’ perspectives, vestibular migraineurs’ needs and expectations are not reflected in non-specialised clinical care, particularly general practice, and frequent misdiagnosis and dismissals create a barrier to timely management of patients’ illnesses. This thesis supports the clinical recommendation of promoting a care plan that extends beyond symptom management and incorporates patient education and management of functional and psychological effects of VM.

BACKGROUND & AIMS: In recent years, the population of persons with hearing loss attending cochlear implant (CI) centres for candidacy discussions has shifted to include those with greater hearing than in the past. Specifically, persons may have residual low frequency hearing ranging from normal to moderately severe with profound loss in the high frequencies (i.e. partial deafness (PD)). To support CI clinicians’ provision of evidence-based recommendations to adults with PD, new clinical outcome data, candidacy guidelines, and predictive factors associated with preservation of acoustic hearing are required to address the following: assessment of speech perception benefits for adults with PD using CIs, quantifying risk for loss of residual hearing, and evaluating outcome by electrode array type. METHOD: This ambidirectional study design used a prospective cohort of adults with PD and two retrospective analyses of adults who received a CI at the Royal Victorian Eye and Ear Hospital (RVEEH). To assess speech perception benefits for adults with PD as compared with traditional CI recipients (defined as severe-to-profound or poorer audiometric thresholds pre-implant), a group of 27 adults with PD were compared to a matched group of traditional CI recipients with all data sourced from the RVEEH database. All recipients were using perimodiolar arrays. To assess hearing preservation outcomes, 154 adults with PD were studied prospectively. These adults were identified as proceeding with the device of interest, a CI with a thin straight electrode array (TSEA). To assess speech perception outcomes by electrode array type, a group of 70 adults with PD using perimodiolar CIs sorted from the database were compared with a group of 63 adults with PD using TSEAs. RESULTS: There were no significant differences in speech perception outcomes for adults with PD compared with those with profound hearing loss who received perimodiolar arrays. Median change in low frequency hearing for adults with PD using a TSEA was -22.5 dB HL. Hearing preservation was assessed further for a subset of 78 defined as having ‘functional’ low frequency hearing pre-implant (≤70 dB HL). For persons who had a pre-implant low frequency pure tone median of ≤45 dB HL, functional hearing was preserved in 75% of cases. No significant differences were found for speech perception outcomes based on electrode array type for the two groups of adults with PD. For persons using a TSEA, it was found that those who had preserved hearing and used electro-acoustic stimulation (EAS) performed significantly better than their peers with electric-only hearing. CONCLUSION: The present study demonstrated that clinicians may use existing CI candidacy guidelines to counsel adults with PD who are considering a CI. The presence of low frequency hearing ≤45 dB HL pre-implant was associated with preservation of functional acoustic hearing in 75% of cases post-implant. Electrode array type was not found to be significantly associated with speech perception outcomes for adults with PD, however those that preserved hearing and used EAS demonstrated superior outcomes. These data provide evidence-based guidelines for counselling adults with PD pre-implant with respect to their potential to benefit and the associated risks to hearing.

The identification of children with language difficulties relies on the referral of children to speech-language services. Yet, the referrers of young school-aged children cannot always accurately discriminate those with and without language difficulties. Consequently, a high proportion of children with language difficulties are never referred for services and many children referred for suspected language difficulties have age-appropriate communication skills. The administration of a short language measure by speech-language therapists or paraprofessionals to identify children who require further language evaluation could improve the accuracy of language service referrals. However, existing short language measures for young school-aged children lack sufficient discrimination capacity. This may be due to the inadequate development of available measures, which have omitted crucial test development steps. The aim of this project was to create a sufficiently accurate, valid and reliable short language measure for children in their first year at school by applying stringent test development procedures.

Patient-centred communication is recognised as the cornerstone to quality healthcare delivery and is associated with positive patient health outcomes. It is a core component of established healthcare disciplines, such as medicine and physiotherapy and is beginning to gain recognition and curriculum space in younger disciplines such as audiology. While there has been a growth in patient communication education in the audiology curricula, studies have reported that students feel ill-prepared when communicating with patients about their hearing impairment. Research remains sparse in exploring the current gaps in communication skills education in audiology. In addition, little is known about student-patient communication in a naturalistic setting such as clinical placements. Therefore, the overarching aim of the research was to explore patient-centred communication in audiology education in an Australian context. This research contains three studies. The first study aimed to examine the perspectives of audiology educators towards patient-centred communication. Semi-structured interviews were conducted with nine audiology program coordinators and key teaching staff to examine the barriers and facilitators to teaching patient-centred communication. Content analysis of the transcribed interviews revealed four emerging themes: professional culture and values, contextual factors, knowledge and understanding of patient-centred communication and individual factors. The findings shed light onto the competing tension between the teaching staff’s value towards patient-centred communication and the biomedically-driven professional culture that places a priority towards technical skills. The aim of the second study was to explore audiology students’ perception of their own clinical communication and learning in the audiology program. In a semi-structured interview using video reflexivity, fifteen students were asked to co-view their own filmed clinical appointment and discuss areas that were most salient to them. Thematic analysis revealed the themes of striving to be patient-centred, assessment shapes behaviour, and power relations to have the biggest influence on students’ own clinical communication. The final theme of what students want uncovered students’ perception towards different teaching methods. These findings showed students’ motivation to demonstrate patient-centred communication can be hindered by conflicting educational standards. The final study examined two interrelated research questions: i) how do audiology students co-construct the communicative tasks in a supervised hearing assessment appointment?; and ii) how does students’ communication align with the principles of patient-centred communication? Final year audiology students from two Australian universities were video-recorded during one of their university-based clinical placements. Two analytical procedures were performed using genre analysis and the development of The Patient-Centred Analytical Framework for Audiology to map students’ patient-centred communication. Findings showed clear communication patterns in how students structured the appointment in the presence of the clinical educator. Students also demonstrated patient-centred communication skills in fostering the relationship and gathering patient information. However, shared decision-making, enablement and responding to patients’ emotional concerns were rarely observed. A significant relationship was found between the clinical educators’ interjection and students’ patient-centred communication patterns. Collectively, these findings identified strengths and gaps in students’ patient-centred communication, and raised questions about the clinical educator’s role in the provision of learning opportunities during the clinical placement. This body of work demonstrated the complexities in teaching and learning patient-centred communication and highlighted the tension between existing barriers and enablers to the implementation of clinical communication education. Irrespective of external barriers, teaching and learning relies on educators’ knowledge and understanding of patient-centred communication. This may include training educators and providing clear guidelines to strengthen the alignment between educational content required for practice, as well as skills to optimise student feedback. To change the technical and biomedical focus within the audiological culture, the development of a unified teaching framework for communication could inform teaching content and assessment rubrics. Ultimately, communication is a skill that requires the opportunity for development. This can be facilitated by integrating communication education longitudinally into the audiology curriculum. Continual reinforcement of communication skills over the course of the program will sustain students’ communication learning and promote skilled communicators.