learning-styles

The Herrmann Brain Dominance Instrument
(HBDI)
The HBDI is a self-report instrument covering the
following types of preference and performance rating:
handedness
strong and weak school subjects
work elements (eg administrative, innovating,
teaching/training)
key descriptors (eg verbal, emotional, factual)
hobbies (eg fishing, photography, travel)
energy level (eg day person, night person)
motion sickness (frequency and connection
with reading)
adjective pairs (forced choice: eg controlled/creative)
introversion/extraversion (nine-point scale)
20 questions (five-point scale: eg ‘I dislike things
uncertain and unpredictable’).
The Flesch-Kincaid readability level of the 20 questions
is 12–13 years and the vocabulary demand of the
work element, key descriptor and adjective pair items
is such that Herrmann provides a 43-item glossary.
This suggests that the instrument will be inaccessible,
without personal mediation, to people with low levels
of basic literacy.
Reliability
The only reliability statistics published by the
Herrmann Group (1989) are test–retest figures, based
on a sample of 78 individuals (see below). The figures
are remarkably high (except for quadrant B), but it
should be noted that no information is provided about
the interval between the two assessments, or about
the feedback that may have been provided after the
first assessment. The test–retest study formed part
of a doctoral dissertation by Ho (unreferenced):
A the rational self:
0.86
B the safe-keeping self:
0.73
C the feeling self:
0.97
D the experimental self:
0.94
introversion/extraversion rating:
0.73.
While short-term test–retest reliability is perhaps
more important than internal consistency in an
instrument of this kind, it is clear that there is
a pressing need for a rigorous independent study
of the reliability of the HBDI.
Validity
Herrmann’s categories appear to have good face,
factorial and construct validity and are claimed to
have catalytic validity when applied in education and
in the business field. However, there have been very
few studies of reliability or validity carried out by
independent researchers, and we have not been able
to locate any longitudinal studies.
As the descriptors in the feedback from a scored
personal profile include many of those used in the
HBDI itself, there is a high probability that respondents
will judge the instrument to have good face validity.
Our own impression is that this is the case, as clusters
of items seem to relate to one’s life experience. The
many individual and group case illustrations provided
by Herrmann in his books also have an authentic quality.
Factorial validity has been established
through the analysis of four data sets, three
carried out by Bunderson (a nationally known
American psychometrician contracted by Herrmann
for the purpose) and one by Ho (unreferenced).
These are presented in some detail in Appendix A
of Herrmann (1989).
Two factor analyses were based on the HBDI items
alone. The first of these was performed on an early,
91-item version of the HBDI, with a sample consisting
of 439 people, including managers, other professionals
and students. Nine factors were extracted, the
first two being bipolar and corresponding to the main
hypothesised dimensions. The most significant item
loadings are presented in Table 26.
The factor loadings were used to establish 12 sets
of item parcels, which were then re-analysed, this time
yielding a two-factor solution which provided an even
better match to Herrmann’s theoretical model and led
to a revision of the item scoring system. A higher-order
left-right dominance factor was also found, supporting
Herrmann’s concept of a closer affinity between
quadrants associated with the same half of the brain
(ie A with B; C with D).
The factor analytic study by Ho (unreferenced) drew
on a sample of 7989 people. This used the current
120-item HBDI and yielded five factors, including
a handedness factor, which was unrelated to the other
four. The first four factors again confirmed Herrmann’s
model and are presented in Table 27.