Assessing Second Language (L2) Productive
Vocabulary in Health Professionals
Joy Williamsa,c, Norman Segalowitza,c,d, Tatsiana Leclaira,c,
Kiyanna Faustina,c & Eva Kehayiab,c,d
aConcordia University, Psychology
bMcGill University, School of Physical and Occupational Therapy
ABSTRACT
STUDY 1
Study 1 tested the validity of a new method for estimating second language (L2) productive
vocabulary size, a method based on the Capture-Recapture (CR) technique borrowed from
population ecology as an estimate of second language (L2) productive vocabulary size
(PVS). Two separate “captures” of productive vocabulary were taken using a word
association task. At Time 1, 47 bilinguals completed the task in English (L1) and French
(L2) by providing word associates to high-frequency stimulus words in each language. At
Time 2, a few days later, the procedure was repeated with different stimulus words. PVS
was calculated using the CR method and compared to the already validated Lex30. The
results indicated both convergent and construct validity for CR: there were significant
positive correlations with Lex30 scores, CR scores indicated that PVSL1>PVSL2 as
expected, and CR scores correlated significantly with the speed of lexical access in the L1
and L2. Results also indicated that whereas CR provides valid estimates of L2 PVS, it does
not indicate absolute vocabulary size. Study 2 (data now being analyzed) is a replication of
Study 1 with methodological improvements plus a measure of second language anxiety in
health communication. Future studies now planned will provide an online version of the
methodology for use with nurses, together with a measure of nurses' second language
communication anxiety, now being developed.
BACKGROUND
A restricted L2 productive vocabulary (words that one can produce, not just understand) is
likely to be one of the limiting factors for nurses and other health professionals having to
use an L2 to communicate with linguistic minority patients, especially in light of the need to
handle culturally sensitive nuances of language.
• A test of L2 productive vocabulary size would be a useful tool for L2 training programs.
• Tests of L2 productive vocabulary size are typically context-dependent, and they limit
production to one correct answer, assess pre-selected targets, and infer vocabulary size
from too small a sample of vocabulary (Milton, 2009). Word associations tasks, however,
do not suffer from these issues (Meara & Fitzpatrick, 2000).
• Meara & Olmos Alcoy (2010) proposed an unconventional approach to measuring
productive vocabulary size based on the logic used in certain population ecology contexts.
The studies reported here investigate the validity of this approach.
THE CAPTURE-RECAPTURE APPROACH
•Traditionally used to provide estimates of animal population size in a given area. The
Petersen Formula (Petersen, 1896) estimates the population size (Figure 1).
Fig. 1: Logic of Capture-Recapture method—Population (vocab size) = C1 x C2 / R
Population
First capture
Population
Time 2
METHOD
Participants:
Bilingual university students (N = 47, 30 females), aged 19-39 yrs. Eligibility
criteria: English L1, French L2. Participants self-reported 80.26% (SD = 12.77)
daily interactions occur in English, and 19.52% (SD = 12.85) occur in French.
Materials:
(a) Living-Nonliving task (lexical access speed; Segalowitz, 2010): computerized
semantic classification task in L1 and L2. Participants decide whether single
words on screen name a living or nonliving object (e.g., bed, stone) by pressing
the appropriate reaction-time key.
(b) Paper-and-pencil word association task (Fig. 2). 30 high-frequency stimulus
words from the 2000 most frequent words in English (Davies & Gardner, 2010)
and French (Lonsdale & Le Bras, 2009).
Fig. 2: Word Association Task (Stimulus + 4 responses shown)
Stimulus word
1
2
3
4
attack
war
castle
guns
weapon
about 4 days
delay, then
TIME 2 Re-capture
L1 Word Association Task
followed by
L2 Word Association Task,
then Lexical Speed Task
Analysis:
Word association data was scored in two ways:
(1) For CR: Use the Petersen formula C1 x C2 / R.
(2) For Lex30: 1 point for each lemma beyond 2000 most frequent (Time 2 data).
Lexical Speed: Reaction times from the Living-Nonliving task.
MAIN RESULTS
(1) L2 CR & Lex30 measures of vocabulary size correlated (r = .66, p <.001).
(All L2 measures were residualized against L1 to correct for individual differences.)
(2) CR measures indicated significant L1 vocabulary size > L2 vocab. size
(L1=980 words, L2 = 709 words. Wilcoxon signed-rank test of the difference,
p
<.001). Lex30 test failed to distinguish L1 from L2 (p = .30).
Second capture
Record 2 values:
- # in Time 2 sample (C2)
- # recaptured from Sample 1 (R)
•
•
•
CR estimate is a valid index of L2 productive vocabulary size.
Word association test is appropriate for use with this
paradigm.
CR index is not, however, a reflection of absolute L1 & L2
vocabulary size.
STUDY 2 (in progress)
The aim of Study 2 is to build on Study 1 by:
• improving the CR methodology by using stimulus words drawn
from a wider range of frequencies within their respective languages,
• to hold the Time 1 & 2 test blocks for a given language within the
same testing session and testing L1 and L2 on different days, and
• administering a test of anxiety for communicating about health in
the first and second language, using a scale newly developed in our
lab.
Data from this study are now being analyzed.
FUTURE STUDY
Procedure:
TIME 1 Capture
L1 Word Association Task
followed by
L2 Word Association Task
dCRIR-JRH
CONCLUSION
Mark and count Time 1 sample (C1)
Return marked
items to
population
Time 1
cCSLP
(3) CR measures associated significantly with lexical access speed
(r = -.44, p = .002) Note: All L2 measures were residualized against L1 to correct for
individual differences.)
A future study is planned that will include the following features:
• Nurse participants with L1 English/L2 French and vice versa
• Online collection of word association data (now being developed)
• Use of Nurse Second Language Anxiety Scale (now in pilot form)
• Online assessment of participants' L2 proficiency and L2 use
Eventually this tool will be integrated into the TRHP language
training activities for evaluating the growth of L2 proficiency in health
professionals working with linguistic minorities.
REFERENCES
1. Davies, M., & Gardner, D. (2010). A frequency dictionary of contemporary
American English: Word sketches, collocates and thematic lists. New York:
Routledge.
2. Lonsdale, D., & Le Bras, Y. (2009). A frequency dictionary of French core
vocabulary for learners. New York: Routledge.
3. Meara, P., & Fitzpatrick, T. (2000) Lex 30: An improved method for assessing
productive vocabulary in an L2. System, 28, 19–30. doi: 10.1016/S0346251X(99)00058-5
4. Meara, P. M., & Olmos Alcoy, J. C. (2010). Words as species: An alternative
approach to estimating productive vocabulary size. Reading in a Foreign
Language, 22, 222–236. Retrieved from http://nflrc.hawaii.edu/rfl
5. Milton, J. (2009). Measuring Second Language Vocabulary Acquisition. Bristol, UK:
Multilingual Matters.
6. Petersen, C. G. J. (1896). The yearly immigration of young plaice into the Linsfjord
from the German Sea. Report of the Danish Biological. Station, 6, 5–84.
7. Segalowitz, N. (2010). The cognitive bases of second language fluency. New York:
Routledge.