Brain Resource International
Database
Validity of Psychometric data
Summary
The results demonstrate that the BRID psychological tests (TM)
provide a highly valid method to assess individual differences and changes
in cognitive function. There were strong correlations with standard paper-and-pencil
measures and the expected differentiation of younger and older individuals.
Introduction
Validity reflects the degree to which a test actually measures
a targeted entity, and it is the ultimate benchmark criterion for any
neurocognitive assessment tool. Even in the context of solid reliability
(see reliability summary) a test or battery of tests that fail(s)
to measure an intended construct provides no added value. We followed
two primary methods for establishing validity:
1. Testing the expected correlations with a previously developed (‘traditional’)
version of the test.
2. Identification of performance differences on the test that exist across
one or more ‘known’ group (eg. it has been established that
older individuals perform more poorly than younger individuals on cognitive
tests that involve mental speed and flexibility).
Subjects
A total of 50 healthy adults completed both:
1) BRID psychological tests (forming IntegNeuro)
2) previously developed cognitive measures typically administered in research
and clinical settings, including paper-and-pencil tests described in detail
in primary textbooks in the field of Neuropsychology and Neurology (Lezak,
etc). These were selected according to the following two criteria: a)
the tests measured the same cognitive construct as the tests of IntegNeuro,
and b) the tests were among the most common cognitive measures (Lezak).
Tests
and Procedure
The IntegNeuro tests include Finger tapping, word generation
(verbal fluency), spot the word test, memory recall, digit span test and
switching of attention.
In one half of the cases (25 individuals), the IntegNeuro
battery was administered at the first visit, and four weeks later the
previously developed paper-and-pencil measures were administered at a
second visit. The other half of the cases (25 individuals), the paper-and-pencil
measures were administered first and IntegNeuro was administered second.
The order of administration (IntegNeuro vs. paper/pencil) was determined
by random assignment to avoid any potential bias.
Validity was assessed by examining the degree of similarity
in performance on both test types. Correlational analyses were computed
for the entire group (50) and separately for individuals under the age
of 46 (range = 22-45) and individuals 46 and older (range = 46-80). The
purpose of the separate analyses for age was to determine with certainty
that the validity of the IntegNeuro measures was not influenced by older
age. Validity was also assessed by examining differences in performances
on the individual tests between young individuals and older individuals.
Results
Correlations: Each IntegNeuro
test was correlated significantly with the relevant paper-and-pencil measure.
In each case, there was a statistically significant degree of overlap
between the two variables (see Table 1). In several cases, the degree
of overlap was extremely substantial (> .75). Importantly, the strength
of the correlations was not affected by age of the participants. All
significant correlations remained when the two groups were examined separately.
Between
group differences: The validity of IntegNeuro was also supported
by the results of the between-group differences. For each IntegNeuro
and equivalent paper-and-pencil measure, the younger individuals performed
statistically better than older individuals.
IntegNeuro test |
Convergent validity measure |
Correlation |
Digit Span |
Digit Span - WAIS III |
.53* |
Spatial Span |
Spatial Span - WMS III |
.63* |
Finger tapping dominant |
Finger Tapping Test |
.55* |
Finger tapping non-dominant |
Finger Tapping Test |
.60* |
Memory recall on the learning trials |
CVLT-R Learning Trials |
.67* |
Memory recall on the short delay |
CVLT-R Short Delay |
.76* |
Memory recall on the delay trial |
CVLT-R Long Delay Free Recall |
.63* |
Letter fluency |
Controlled Oral Word Association |
.77* |
Animal fluency |
Animal fluency |
.76* |
Spot the Word |
WAIS III Full Scale IQ |
.63* |
Switching of attention A |
Trail Making Test A |
.53* |
Switching of attention B |
Trail Making Test B |
.65* |
Mazes
Number of Correct Trials
Number of Errors
Maze Time |
Rey Complex Figure Test
Delay
Delay
Delay |
-.15
-.42*
-.65*
|
Verbal Interference |
Stroop |
.70* |
Choice Reaction Time |
Finger Tapping Dominant |
-.53* |
Working Memory Test |
ARCPT |
.55* |
|
|
|
|
*Statistically significant association between the two variables.
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