English proficiency, intelligibility, and participation of multilingual speakers in Australia

Proficiency in Spoken English has implications for the ability of multilingual speakers to participate in vocational, educational, and social activities in English-dominant countries. A key component of spoken language proficiency is intelligibility, a relative measure of how much of an individual’s speech is understood by their listener. This doctoral research aimed to investigate the relationship between multilingual speakers’ English proficiency, intelligibility, and participation in Australian society and provide insight into whether intelligibility enhancement is an effective intervention to improve English intelligibility in multilingual speakers.
This doctoral research contains four parts presented as a series of eight publications; one encyclopaedia entry and seven journal articles. Part One provides an orientation to the thesis and includes a literature review (Paper 1) describing the World Health Organization’s International Classification of Functioning, Disability and Health (ICF) and its application to speech, language, and hearing. The ICF provided the theoretical framework for this research and ensured a holistic focus on participation.
Part Two (Papers 2 to 5) examines the participation of multilingual speakers in Australia from the perspective of their English proficiency and intelligibility. Paper 2 analysed data from over 19 million people in the 2006 and 2011 censuses to explore the relationship between spoken English proficiency and education, employment, and income. Multilingual residents who spoke English very well were more likely to have postgraduate qualifications, full-time employment and high income than monolingual English-speaking Australians. Paper 3 analysed data from Building a New Life in Australia: The Longitudinal Study of Humanitarian Migrants to examine 2,399 refugees’ English proficiency and how it facilitated or hindered self-sufficiency (e.g., knowing how to look for a job) and successful settlement in Australia. Oral English proficiency proved a statistically significant predictor of self-sufficiency, explaining 21% of the variance while controlling for confounding variables such as age and education. Paper 4 analysed survey data from 137 multilingual students enrolled at 14 Australian universities regarding perceptions of the impact of spoken English proficiency and intelligibility on participation, not only at university, but in society. While participants reported spoken English proficiency impacted participation, they indicated a lack of awareness of intelligibility influencing spoken language proficiency. The amount of time multilingual students had spent studying English had less effect on outcomes than the amount of time they had spent speaking English in conversations with native speakers. Paper 5 further explored university students’ perspectives of English intelligibility through qualitative analysis. Data included open-ended comments from the survey in Paper 4, as well as semi-structured interviews with six students and one faculty member from one university. Motivations for improving intelligibility were career aspirations and meeting their own and others’ expectations. Barriers to intelligible speech included lack of self-awareness of intelligibility and use of ineffective strategies (e.g., fast speech rate to disguise pronunciation difficulties). Facilitators of intelligible speech were support from others, beneficial strategies (e.g., confirming listener understanding), and opportunities to practice.
Part Three (Papers 6, 7, and 8) examines intelligibility enhancement, an intervention designed to improve English intelligibility in multilingual speakers. Paper 6 presented an overview of intelligibility enhancement. Paper 7 used a retrospective record review of 175 client records from a university clinic providing intelligibility enhancement to describe characteristics of multilingual speakers who sought support for English intelligibility. The results highlighted the broad range of factors contributing to multilingual speakers’ intelligibility in English (e.g., substitutions/deletions, speaking volume, and time spent using English in conversations). Paper 8 used a multiple-baseline single-case experimental design with two multilingual university students and demonstrated the effectiveness of the Intelligibility Enhancement Assessment and Intervention Protocols. Following intervention, both participants displayed increased performance across the speech/intelligibility instruments in the protocol.
Part Four of the thesis presents conclusions and contributions of this research. This research has shown that multilingual speakers: were successfully participating in Australian society, while also contributing to Australia’s economic and social prosperity; perceived a strong relationship between their English proficiency and their successful participation in society; lacked awareness of their intelligibility and its importance to their spoken language proficiency; valued intervention to support their intelligibility in English; and achieved positive outcomes after participating in intervention with an SLP using the Intelligibility Enhancement Assessment and Intervention Protocols (Blake, 2019a, 2019b). This doctoral research provides a new and significant contribution to knowledge of English proficiency, intelligibility, and participation in multilingual speakers in Australia. The findings provide insights for communities, universities, and individuals, as well as for SLPs who support multilingual speakers in intelligibility enhancement or other contexts of speech-language pathology in Australia and other language-dominant countries.