Open Journal of Medical Psychology, 2013, 2, 11-16
doi:10.4236/ojmp.2013.24B003 Published Online October 2013 (http://www.scirp.org/journal/ojmp)
Test-Retest Reliability, Convergent Validity and Practice
Effects of the RBANS in a Memory Clinic Setting:
A Pilot Study
Yanhong Dong1,2,3, Claire L. Thompson4, Shi Huey Joanne Tan2, Leon Ben Swie Lim1,2,
Wanshin Pang1,2, Christopher Li-Hsian Chen1,2
1Memory Aging and Cognition Centre, Department of Pharmacology, National University Health System, Singapore
2Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
3Centre for Healthy Brain Ageing and Dementia Collaborative Research Centre, School of Psychiatry,
the University of New South Wales, Australia
4James Cook University (Australia), Singapore Campus
Received June, 2013
This pilot study examined the psychometric properties and clinical utility of a brief neuropsychological instrument
(Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The test-retest reliability, practice ef-
fects and convergent validity of RBANS were examined in participants without objective cognitive impairment. The
tests were administered at two time points at approximately a two weeks’ interval, with 30 cognitively intact partici-
pants with a mean age of 63.3 ± 5.8 years. Adequate test-retest reliabilities were found for RBANS subtests, index and
total scale scores with significant gain scores in immediate memory and visuospatial function. The RBANS showed
good convergent validity and the RBANS supplemented with executive and language measures (Colour Trails Test and
30-item modified Boston Naming Test, respectively) demonstrated excellent convergent validity with a formal neuro-
psychological battery. This pilot study has provided the preliminary evidence of reliability and convergent validity of
the RBANS. Additionally, it also provides insight on the practice effects so that clinicians may assess significant
changes in RBANS subtests and domain indexes for clinical practice.
Keywords: RBANS; Neuropsychological Tests; Test-retest Reliability; Validity; Practice Effect
The prevalence of dementia is estimated to be 35.6
mil-lion patients in 2 010 and is expected to double every
20 years , thereby creating increasing demand for an
efficient, reliable and valid instrument for the early de-
tection of age-related cognitive impairments. This in-
strument should have the following characteristics: 1)
brevity- elderly people with cognitive impairment may
only co-operate well with cogn itive testing within a short
span of time ; 2) test-retest reliability- repeated cogni-
tive testing is often required to clarify diagnosis or to
monitor progression of symptoms ; and 3) demon-
strates convergent validity with a formal neuropsy-
chological battery, which covers a range of cognitive
domains required for the diagnosis of dementia.
The Repeatable Battery for the Assessment of Neu-
ropsychological Status (RBANS) has demonstrated its
reliabilities and validities in the western population and
may be considered for the detection of dementia in Sin-
gapore. The RBANS is brief and takes approximately 30
minutes . It assesses a total of five cognitive domains
with 12 subtests . RBANS has shown sensitivity of
84% and specificity of 97% for cognitive impairment in
Alzheimer’s disease (AD) . However, RBANS was
limited in detecting Mild Cognitive Impairment (MCI),
as the sum of index scores and six of the subtests (list
learning, semantic fluency, coding, list recall, story recall
and figure recall) had poor sensitivity (range: 8 – 24%) in
detecting MCI. Also, the lack of adequate executive
function measures and object naming tasks  has been
criticized as the drawback of RBANS for differential
diagnosis of cognitive impairment in a clinical setting.
Therefore, in the current study, we supplemented
RBANS with the Color Trails Test (CTT) and the
30-item modified Boston Naming Test (mBNT) to
address these drawbacks.
Information on test-retest reliability of the RBANS is
limited. Test-retest reliability is first established using
cognitively normal particip ants . A short span of time
Copyright © 2013 SciRes. OJMP
Y. H. DONG ET AL.
interval (under one month) minimizes the degree to
which individuals will go through any physical or psy-
chological changes and therefore is more accurate to as-
sess the reliability of the cognitive instrument .
However, short intervals may introduce practice effects.
For the RBANS, studies with heterogeneous samples
with and without cognitive impairment have reported
test-retest reliability of 0.96 over one month in China
, and of 0.72 over a three month interval in Brazil
. Pat-ton et al.  reported stable scores over
one-year and two-year intervals but test-retest reliability
coefficients were not reported. Therefore, this study will
evaluate the test-retest reliability of the RBANS and
examine its practice effect over a two-week period in
Singaporean older adult participants with no objective
cognitive impairment (NCI). In addition, the convergent
validity of the RBANS will be assessed by the correla-
tion with a locally validated formal neuropsychological
battery for Singaporean elderly .
The hypotheses of this pilot study were: 1) RBANS
and RBANS supplemented with CTT and m-BNT wou ld
demonstrate good test-retest reliability over a two-week
period; 2) There would be evident practice effects re-
flected by the gain scores of the individual subtest scores
and domain index scores; and 3) RBANS and RBANS
supplemented with CTT and m-BNT would demonstrate
good convergent validity with a formal neuropsy-
We recruited 30 participants with no objective cognitive
impairment determined by a formal neuropsychological
battery. Of these, 7 were recruited from a memory clinic
at the National University Health System (NUHS) in
Singapore and a further 23 were volunteers from the
community. Inclusion criteria included a minimum age
of 50 years and absence of major psychiatric or physical
illness and/ or sensory impairment. Two participants de-
layed their second assessment for 114 days and were
therefore excluded from the analyses. This study was
approved by National Healthcare Group Domain-Spe-
cific Review Board (DSRB), and was conducted in con-
formity with the Declaration of Helsinki. Written in-
formed consent was obtained from all participants.
All subtests of the RBANS were scored according to
standardized criteria except for Figure Copy and Figure
Recall, which were scored according to Duff et al.’s
modified criteria . Raw scores of the 12 subtests
were converted to age and education adjusted scaled
scores  before calculating an Index score for each
domain. The Sum of Index score was then converted to a
Total Scale score, with a mean of 100 and standard de-
viation of 15. The Color Trails Test (CTT)[9,18] and
30-item modified Boston Naming Test  were admin-
istered as supplementary tests to th e RBANS.
Participants were also assessed using a formal neuro-
psychological battery locally validated for Singaporean
elderly . This battery covers 7 cognitive domains in-
cluding both non-memory and memory domains. The
non-memory domains of the formal neuropsychological
battery included: (1) attention (d igit span test), visual
span test and auditory detection test; (2) lan-
guage (15-item modified Boston naming) and cate-
gory fluency; (3) visuomotor speed (symbol digit
modalities, digit cancellation, and mazes; (4)
visuoconstruction (visual reproduction subtest of the
Wechsler Memory Scale- Revised copy task, clock
drawing and the Block Design subtest of the
Wechsler Adult Intelligence Scale Revised; (5) ex-
ecutive function (Frontal Assessment Battery). The
memory domains of the battery included: (1) verbal
memory (word list ; and story recall ; (2) visual
memory (picture recall ) and the visual reproduction
subtest of the Wechsler Memory Scale-Revised .
In addition, routine brief cognitive screening meas-
ures, the Abbreviated Mental Test (AMT), the Mini-
Mental State Examination (MMSE) and the Montreal
Cognitive Assessment (MoCA) were ad-ministered
to all participants. The 15-item Geriatric De-pression
Scale (GDS ) was administered to screen for depres-
The assessments and re-testing were administered by
trained research psychologists in accordance with the
manual over approximately two weeks.
2.4. Statistical Analysis
The descriptive statistics were used to characterize the
sample’s demographic and clinical profile. Pearson’s
correlation coefficients were calculated between Time 1
and Time 2 to examine test-retest reliability and conver-
gent validity of the cognitive tests. Practice effects were
expressed as effect sizes and calculated by the change in
raw subtest scores, index scores and total scale scores
between time 1 and time 2 divided by the standard devia-
tion of time 1 scores. This method has been com-
monly used [35,36].
3.1. Sample Characteristics
Participants had a mean age of 63.3 ± 5.8 years with 12.3
Copyright © 2013 SciRes. OJMP
Y. H. DONG ET AL.
Copyright © 2013 SciRes. OJMP
± 4.9 years of education (see Table 1). Most were Chi-
nese (96.4%) females (67.9%). Participants’ mean scores
of brief cognitive screening tests (AMT, MMSE and
MoCA) were within normal range. No participants re-
ported significant symptoms of depression (GDS score:
1.39 ± 1.62). The mean test-retest interval was approxi-
mately two weeks (15.6 4 ± 4.72 days).
3.2. Test-retest Reliability of the RBANS
The means and standard deviations for the RBANS at
each time point, along with the Pearson's correlations are
presented in Ta bl e 2 . Significant correlations were found
between times 1 and time 2 raw scores for all subtests
except list recall. Further examination of the list recall
subtest revealed three outliers. Excluding these outliers
led to significant correlation s between list recall scores at
time 1 and time 2 (r = .608, p = .001). The addition al two
tests used to supplement the RBANS (CTT and mBNT)
also demonstrated adequate test-retest reliability (see
3.3. Gain Scores and Practice Effects from Time
1 to Time 2
As shown in Table 2, there were significant gain scores
for five of the twelve subtests: list learning and list recall,
story memory, figure copy and figure recall with moder-
ate to large effect sizes (.45 - .87). Additionally, signifi-
cant gain scores were observed in the domain index
scores of visuospatial function, immediate memory and
delayed memory. There were no significant gain scores
in total scale scores of RBANS or the supplementary
tests (CTT and mBNT).
Table 1. Demographic characteristics.
Variables N = 28
Age 63.29 (5.84)
Years education 12.32 (4.87)
Gender (n, %)
Males 9 (32.1%)
Females 19 (67.9%)
Chinese (n, %) 27 (96.4%)
Eurasian (n, %) 1 (3.6%)
AMT 9.68 (0.48)
MMSE 27.96 (1.45)
MoCA 26.64 (2.36)
Retest Interval (days) 15.64 (4.72)
Values are mean (SD) unless otherwise specified.
Table 2. The test-retest indices of RBANS subte sts, supple m e ntary te sts (CTT and mBNT), index and total scale scores.
Time 1 M (SD) Time 2 M (SD) Pearson CorrelationTime 2 – Time 1 Effect Size
List learning 27.18 (5.61) 32.07 (4.97) 0.78*** 4.89*** 0.87
Story memory 18.82 (3.51) 20.68 (3.57) 0.83*** 1.86*** 0.53
Figure copy 17.46 (2.08) 16.00 (2.67) 0.65*** -1.46*** -0.70
Line orientation 16.57 (3.28) 16.29 (3.10) 0.76*** -0.29 -0.09
Picture naming 9.46 (0.79) 9.50 (0.69) 0.71*** 0.04 0.05
Semantic fluency 18.82 (4.27) 19.14 (3.30) 0.70*** 0.32 0.07
Digit span 11.29 (2.57) 10.75 (2.69) 0.71*** -0.54 -0.21
Coding 42.11 (9.25) 43.54 (11.22) 0.82*** 1.43 0.15
List recall 6.25 (3.15) 8.14 (1.58) 0.36 1.89** 0.60
List recognition 19.68 (0.55) 19.43 (1.14) 0.47* -0.25 -0.45
Story recall 10.18 (1.72) 10.43 (1.60) 0.77*** 0.25 0.15
Figure recall 12.68 (3.57) 14.29 (3.43) 0.63*** 1.61** 0.45
CTT1 (seconds) 50.75 (20.00) 47.14 (21.11) 0.57** -3.61 -0.18
CTT2 (seconds) 96.07 (30.57) 89.32 (22.70) 0.67*** -6.75 -0.22
30-item mBNT 25.90 (3.64) 26.18 (3.69) 0.90*** 0.29 0.08
Attention 94.36 (14.56) 93.25 (14.41) 0.76*** -1.11 -0.08
Language 96.68 (19.80) 98.50 (21.19) 0.55** 1.82 0.09
Visuospatial 100.96 (13.08) 96.19 (10.16) 0.58** -4.77* -0.36
Immediate memory 100.43 (13.81) 115.90 (11.82) 0.50* 15.48*** 1.12
Delayed memory 100.19 (13.40) 105.31 (14.00) 0.55** 5.12 0.38
Total Scale 98.07 (17.62) 101.89 (16.07) 0.80*** 3.82 0.22
RBANS: Repeatable Battery for the Assessment of Neuropsychological Status; CTT: Color Trails Test; mBNT: modified Boston Naming Test; SD: Standard
Deviation. Eff ect Size: (Time 2 – Time 1) / Tim e 1’s SD. * p < 0.05 ; * * p < 0.01; *** p < 0.001
Y. H. DONG ET AL.
3.4. Convergent Validity of the Tests
As shown in Tabl e 3, at time 1 the RBANS had a strong
correlation with the composite z scores of RBANS sup-
plemented with the CTT and mBNT (r = .83, p < .001)
while the strength of a significant correlation between the
RBANS and a formal neuropsychological battery was
relatively weaker (r = .61, p = .001). However, the cor-
relation between the composite z scores of the RBANS
supplemented with CTT and mBNT and the formal
neuropsychological battery was strong (r = .80, p
In this pilot study, we have examined the test-retest reli-
ability, practice effects and co nvergent validity of a brief
neuropsychological battery, the RBANS, in a sample of
cognitively intact older adults in Singapore. The princi-
pal findings of this study include: 1) the RBANS has
good test-retest reliability and conv ergent validity; an d 2)
the practice effects of the RBANS are evident in visu-
ospatial function and memory domains.
The first hypothesis is supported, that is, the RBANS
alone has demonstrated acceptable test-retest reliability
for clinical purposes. In addition, RBANS supplemented
with CTT and mBNT demonstrated excellent test-retest
reliability. These results are consisten t with the generally
sound psychometric properties of the scales as previously
reported. Test-retest reliability was also significant in 11
out of 12 RBANS subtests. Interestingly, the reliability
coefficient for the remaining subtest (list recall) attained
significance when three outlying cases were removed
from the analysis. These three cases all scored a zero at
time 1, and scored highly at time 2, which may possibly
reflect test anxiety affecting their performance at time 1
but not at time 2. Also of clinical interest is the finding of
significant gain scores on many (but not all) of the
RBANS subtests, while overall scores show little gain.
The second hypothesis was partially supported. The
RBANS showed moderate to large practice effects in
visuospatial function, immediate memory and delayed
memory. The practice effect in immediate memory is
consistent with a previou s study on the practice effects of
RBANS in a community sample of older adults in a
Table 3. Correlations of the total scale scores of RBANS,
composite Z scores of RBANS supplemented w ith CTT and
mBNT and composite Z scores of a formal neuropsy-
1. RBANS -
2. RBANS with CTT and mBNT 0.83*** -
3. Formal Neurop sy chological battery 0.61** 0.80***
**p < 0.01; ***p < 0.001.
western population. However, the practice effects
demonstrated in visuospatial function differed from the
previous study, which may be explained by different
sample characteristics such as age (younger participants
in the current study compared to the older participants in
previous study: 63.29 ± 5.84 vs 72.89 ± 5.52). In
addition, the different finding may be attributed to dif-
ferent test-retest interval (a short interval of 2 weeks in
the cur-rent study compared to a longer interval of 38
weeks in the previous study ).
The third hypothesis was also confirmed. The RBA NS
showed adequate convergent validity with the formal
neuropsychological battery. Moreover, the RBANS sup-
plemented with CTT and mBNT has dem-onstrated ex-
cellent convergent validity. This result is en couraging, in
that it suggests the RBANS may be an appropriate sub-
stitute for the lengthier neuropsychologi-cal test batteries
in memory disorders clinics.
The novelty of this study inclu des the following. First,
few studies to date have investigated the clinical utility of
a brief neuropsychological test battery. The findings of
this study support the use of the RBANS as an assess-
ment instrument in clinical as well as research set-tings.
The inclusion of CTT and mBNT further improves the
psychometric properties such as test-retest reliability and
convergent validity. Consequently, these two tests will
add clinical value to the RBANS. This study has also
reported valuable clinical data on the expected gain
scores resulting from practice effects on the RBANS.
This will provide insights for clinicians to observe for
significant changes in raw subtest scores and index
scores of RBANS. Second, a particular strength of this
study is the complete data set, free from attrition which
sometimes limits the ability to interpret results of re-
peated measures studies. However there were a number
of ceiling effects identified in the data, which may have
contributed to non-significant results. Such ceiling ef-
fects are to be expected in cogn itively intact participants,
yet reliability and validity of tests should be first estab-
lished with cognitively intact participants prior to the
implementation in clinical popu lations.
There are several limitations in this study. First, the
sample size is small; we only recruited 30 cognitively
intact participants with 28 participants included for
analysis, as this was a pilot study. A larger sample size is
required in future studies. Second, we did not examine
the test-retest reliability, convergen t validity and practice
effects in older adults with cognitive impairment, again
due to the nature of a pilot study. Older adults with cog-
nitive impairment may have different rate of cognitive
decline or improvement compared to healthy controls.
Therefore, our findings are limited to cognitively intact
older adults. Future studies should include older adults
with a range of cognitive statu s to examine the test-retest
Copyright © 2013 SciRes. OJMP
Y. H. DONG ET AL. 15
reliability, convergent validity and practice effects of the
RBANS. Third, the test-retest interval was short, at a
span of 2 weeks, and may not be in line with clinical
practice of repeat testing at 6 months or a year. Therefore,
future studies with a longer span of test-retest duration
will provide more information about the RBANS for
In conclusion, The RBANS has good test-retest reli-
ability and convergent validity, while RBANS supple-
mented with CTT and mBNT have demonstrated excel-
lent convergent validity. In addition, the practice effects
were only demonstrated in immediate memory and visu-
ospatial function while other index and total scale scores
are spared of practice effects within the short span of a
2-week interval. Therefore, RBANS or RBANS supple-
mented with CTT and mBNT may be adopted for routine
clinical practice in memory clinics.
This study is funded by a Memory Ageing Cognition
Center (MACC) pilot grant (NMRC/CG/NUHS/ 2010)
from the National Medical Research Council of Singa-
pore. Y. Dong is currently receiving research support
under the NMRC fellowship training award. The authors
thank the research team from NUHS MACC for data
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