Articulation and phonological impairments are frequent in the child population, affecting up to 15% of preschoolers and 6% of elementary school children in the USA (ASHA, 1995). According to a recent report, the prevalence of communication disorders in Australia, inclusive of difficulties with articulation, was between 12.40% and 13.04% (Mcleod & McKinnon, 2007). The prevalence of phonological disorder in Malaysia remains unknown. However, referring to the average prevalence worldwide, the prevalence of phonological disorder is expected to be similarly high in Malaysia. Therefore, clients with speech impairments are likely to be a common occurrence in Malaysian SLPs’ caseloads. In spite of this, there is limited documented data which are not sufficient to describe the phonological patterns of both MalE speaking adults and children. Thus, it is difficult to distinguish a speech difference from a speech disorder. Many SLPs in Malaysia may not completely understand the phonological patterns of MalE, and this may lead to difficulty with accurate diagnosis for these speakers. Undoubtedly, MalE speakers have distinctive and predictable characteristics that are different from those of so-called SE, but these variations will reflect differences not delays or deficiencies. Therefore, it is important to discover how SLPs in Malaysia assess their speech impaired clients given the absence of culturally appropriate
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assessment tools. A first step towards exploring the area of phonological assessment for Malaysian English speaking children is needed.
The first aim of this thesis is to survey a wide sample of Malaysian SLPs in order: 1. To determine the types of articulation and phonological assessment currently
used by Malaysian SLPs.
2. To investigate the adequacy and accuracy of current articulation and phonological assessment in meeting clinical needs.
3. To describe the experiences of SLPs in using current articulation and phonological assessments.
4. To explore the need for further research in the areas of articulation and phonology.
Subsequent to this, it is also important to gather information about the characteristics of the consonant and vowel realizations of adult MalE speakers. The MalE phonological patterns exhibited by adult speakers will be regarded as a normal variation or dialectal phonology of MalE. This information is important because SLPs will then have data to rely on when distinguishing a language difference that is due to MalE variation from a language disorder.
The second aim of this thesis therefore is to provide an explicit description of MalE phonology by using a quantitative auditory phonetic analysis. The specific goals are:
1. To investigate the consonant and vowel inventories of MalE.
2. To investigate the characteristics of the consonant and vowel realizations of MalE in terms of types and occurrence.
3. To investigate the possible influences and interference patterns within MalE. 4. To compare the phonological patterns of MalE with major phonological
processes exhibited by SE speaking children in order to distinguish dialectal phonological processes from developmental phonological processes.
Due to the absence of local normative data in phonology for Malaysian children, Malaysian SLPs are asking for reliable and valid normative data for MalE speaking children. This normative data are necessary in order to identify MalE speaking children with phonological impairments. Materials from the first and second aims will provide the background information for the major section of the thesis.
To date, little is known about the phonological development of MalE English speaking children. The third aim and also the major aim of this thesis are to provide
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valid and reliable normative data for the phonological development of MalE in Malaysian Chinese children between the ages of 3 and 7 years. Under this aim, the following specific objectives are addressed with respect to Malaysian Chinese children who are learning MalE from an early age:
A) Age of Speech Sound Acquisition
1. To determine the age of customary production and mastery production of i) different MalE consonants in syllable initial (SI) and final (SF) positions; ii) MalE vowels;
iii) MalE consonant clusters in SI and SF.
2. To compare the age of speech sound acquisition in MalE with Standard English (SE).
B) Speech Sound Accuracy
1. To determine the speech production accuracy in terms of Percentage of Consonants Correct (PCC), Percentage of Vowels Correct (PVC) and Percentage of Consonant Clusters Correct (PCCC) at different ages when assessed with and without taking MalE dialectal features into consideration. 2. To investigate whether there are significant differences between PCC, PVC and
PCCC at different ages when assessed with and without taking MalE dialectal features into consideration.
3. To examine any sex and age effect in terms of PCC, PVC and PCCC. 4. To compare the speech sound accuracy in MalE with SE.
5. To determine the accuracy of consonants according to i) different sound classes, ii) syllable positions and iii) phonetic similarities at different ages.
6. To determine the accuracy of vowels according to syllable type.
7. To determine the accuracy of consonant clusters according to i) syllable positions, ii) cluster categories and iii) number of cluster constituents.
C) Phonological Processes
1. To examine the types and occurrence of dialectal and developmental phonological processes exhibited by MalE speaking children.
2. To examine any significant differences in sex and age effects on the occurrence of phonological processes.
3. To determine the age of suppression for developmental phonological processes. 4. To compare the age of suppression for developmental phonological processes in MalE with Standard English (SE).
52 The outline of the present thesis is: Chapter 1: Literature review
Chapter 2: Surveying the perception of Malaysian SLPs in articulation and phonological assessments (First aims)
Chapter 3: Investigating the phonological features of Malaysian English in adult speakers (Second aims)
Chapter 4: Methodology for the normative study of children’s phonological development
Chapter 5: Age of speech sound acquisition (Third aims part i) Chapter 6: Speech sound accuracy (Third aims part ii)
Chapter 7: Phonological processes (Third aims part ii) Chapter 8: General discussion
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CHAPTER 2
SURVEYING THE PERCEPTION OF MALAYSIAN SPEECH-LANGUAGE PATHOLOGISTS IN ARTICULATION AND PHONOLOGICAL
ASSESSMENTS
2.0 INTRODUCTION
The lack of culturally appropriate and sensitive assessment tools for assessing Malaysian children with speech and language disorders has been highlighted (Lian & Abdullah, 2001; Low, 2006). To compensate for the lack of appropriate assessment tools, most of the Malaysian SLPs use informal assessment procedures to identify the children’s general communicative competence rather than specific linguistic skills (van Dort, 2005). In a situation where linguistics skills are not properly assessed, it will lead to consequences of either over or under-diagnosis. Given the absence of culturally appropriate assessment tools in Malaysia, it will be worthwhile to investigate the perception of Malaysian SLPs about articulation and phonology assessments which involve linguistic components. The first aim of this thesis is to survey a wide sample of Malaysian SLPs in order to:
1. Determine the types of articulation and phonological assessment currently used by Malaysian SLPs
2. Investigate the adequacy and accuracy of current articulation and phonological assessment in meeting clinical needs
3. Describe the experiences of SLPs in using current articulation and phonological assessments
4. Explore the need for further research in the areas of articulation and phonology.