JCPSLP Vol 18 No 3 2016

26 / 156

128 JCPSLP Volume 18, Number 3 2016 Journal of Clinical Practice in Speech-Language Pathology
such as bầm, bu, má, mạ, mệ, mợ, and u;
• be used currently in the speech of people within Viet
Nam. For example, the traditional word for box was
rương; however, it was not selected because hộp or
thùng is used more commonly now;
• be culturally sensitive in both word choice and picture.
For example, the word đũa (chopsticks) was selected
rather than dao (knife) because seeing an image of a
knife may scare young children;
• be picturable so young children can recognise the word
easily and spontaneously name the word. The images
were considered to be contrastable to differentiate
meanings. For example, the word gà (chicken) was
selected for the initial consonant /ɣ/ so the word chim
(bird) was not selected for the initial consonant /c/
because of the possible confusion between these
two images. Another example, the word phở (thinly
sliced noodle soup) was seen as a good word choice
containing the initial consonant /f/ but was not selected
because of the possible confusion with the word bún
(round noodle soup);
• be selected from basic syntactic forms such as nouns
(66 out of 77 words) and verbs (11 out of 77 words).
Presentation
The VSA consists of 77 monosyllabic words represented by
77 colour pictures. The order of the word list was based on
initial consonants. Proposed prototypes for the 77 pictures
were discussed by the VSA authors, then were sent to a
Vietnamese artist to be drawn. The 77 pictures were bound
in a picture booklet. The front page displays a picture
illustrating a word and the orthography of the word (see
Figure 2). On the back page, there is a small picture of the
word plus full phonetic transcriptions of Standard
Vietnamese, Northern, Central, and Southern Vietnamese
as well as the prompts to elicit the word (see Figure 3).
Test administration
The VSA was designed to be administered in a
standardised manner. The assessment can be administered
in research and clinical settings. Instructions will be
Northern, Central and Southern dialects was collated based
on an extensive literature review (Pha. m & McLeod, 2016).
The following Vietnamese speech sounds were included in
the VSA based on the review:
• 23 initial consonants in Standard Vietnamese /p, b, t̪ʰ, t,
d, ʈ, c, k, ʔ, m, n, ɲ, ŋ, f, v, s, ʂ, z, ʐ,, x, ɣ , h, l/ and four
variants including /ts, r/ in the Northern dialect and /w, j/
in the Southern dialect;
• 6 final consonants in Standard Vietnamese /p, t, k, m, n,
ŋ/ and four variants across three dialects /c, ɲ, kp, ŋm/;
• 2 final semivowels /w, j/;
• 1 medial semivowel/approximant /w/ in Standard
Vietnamese and three dialects;
• 16 vowels in Standard Vietnamese (including nine long
singleton vowels /i, e, ɛ, ɯ, u, o, ɔ, ɤ, ɑ/, four short
singleton vowels /ɑ̆, ɤ̆, ɛ̆, ɔ̆/, three diphthongs /ie, uo,
ɯɤ/, and ten variants /ĭ, ɨ, ĕ, ŏ, ŭ, ɔː, oː, uː, ɛː, ɤː/
across three dialects;
• 6 tones in Standard Vietnamese and two variants of the
tone 5 and 6 occurring in syllables ending by voiceless
plosive consonants /p, t, k/ in three dialects.
Elicitation of each Vietnamese speech sound
Typically each speech sound is elicited in between one and
five stimuli in single word sampling tools (McLeod, 2012b).
Researchers have recommended there be at least two
words in a single word task containing each phoneme in
order to determine the consistency of production or
phoneme stabilisation (Eisenberg & Hitchcock, 2010; Hua,
2002). Therefore, at least two stimuli were selected for each
phoneme (consonants, vowels, and tones) shared across
all dialects in the VSA. For example, the two selected words
beginning with /k/ that were pronounced consistently
across all dialects were: kẹo (candy) /kɛw 6/, and cổ (neck)
/ko4/. The authors attempted to avoid excessive use of any
consonant, vowel, or tone within the word list.
The selection of words also took into consideration different
phonetic contexts in Vietnamese. Different phoneme
sequence constraints were considered so as to
accommodate variability in terms of syllable shapes, rimes,
phonotactic variants, and tones within the child’s
production rule system. It was important to accommodate
the effect of coarticulation of front and back vowels on the
production of initial and final consonants (Cao, 2006; Đoàn,
2003). Therefore, it was decided that the two words in the
VSA containing the same initial consonants should be
followed by a front and back vowel. For example, the
selected words beginning with the initial consonant /b/
contained a front vowel bí (pumkin) /bi5/, and back vowel
bảng (board) /bɑŋ 4/. In addition, the VSA authors
considered the effect of coarticulation of rounded and
unrounded vowels on the production of final consonants
/k, ŋ / with back vowels (Cao, 2006; Đoàn, 2003). For
example, the word bụng (belly) /bŭŋm6/ was added to the
set of words beginning with initial consonant /b/.
Word selection
Within the VSA the selected words met following criteria.
They had to:
• be within the vocabulary range of Vietnamese-speaking
children in Viet Nam, Australia, and USA so that children
can produce the word spontaneously as often as
possible;
• be used frequently by the entire population throughout
Viet Nam. Therefore, words having lexical variants were
excluded. For example, the word mẹ (mother) was not
selected because of variants used in different regions
Figure 2. The front page for the stimulus item nón (cone hat).
Figure 3. The back page for the stimulus item nón (cone hat).