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Project no: nr9035
Publication title: Improving the validity of competency-based
assessment
This study considers the status of validity in the context of vocational
education and training (VET) in Australia. This has involved reviewing
the literature, reporting on case studies, presenting key findings and
recommending a tool to guide assessors.
The study reports that while validity is an issue that has been considered
in previous Australian studies, the approach used has been based upon
early models developed in the United States that are now believed to be
inadequate. The study therefore turns to more recent approaches to validity
to examine their suitability for the Australian environment of competency-based
assessment.
One of these approaches takes validity as a unitary entity which, nevertheless
can be viewed in a variety of ways: it presents various aspects or facets
to which users of assessment outcomes might appeal in seeking to establish
the soundness (or otherwise) of the interpretations they make. Thus the
focus is shifted from the validity of an individual assessment instrument
to the broader issue of the validity of the interpretation and
use of an assessment outcome. The eight facets of validity proposed
by Nitko (1996) are the focus of the study.
This approach to validity is examined in the context of the following
questions:
- Are these proposed facets of validity meaningful for the competency-based
assessment approach now used in Australias vocational education
and training system?
- For a sample of practitioners, to what extent are these expanded notions
of validity already familiar?
- If the notions are familiar, are there clear benefits for assessments
to be derived from an acceptance and use of this approach to validity?
- Can a diagnostic tool be devised to facilitate use of
this approach to validity?
Two groups were identified to be included in the study: organisations
that both assess and train assessors at certificate and diploma level,
and companies within the retail industry. Six case studies were carried
out.
Each case study involved:
- matching the assessment procedures used against industry standards
- study of the organisations assessment guidelines and instruments
and judging them against published national guidelines and assessment
component requirements
- interviews with representatives of participating organisations
- preparation of confidential evaluations of assessment procedures (returned
to participants and not included in the report)
- preparation of final summaries of each organisations input (approved
by the participating organisations)
The eight-facet approach to validity leads to the identification of eight
different kinds of evidence. The report then shows how each of these kinds
of evidence, namely:
- representativeness of content
- relationships among the assessment tasks (internal coherence)
- relationships of assessment results to other variables (external
coherence)
- reliability of assessors and of the assessment over time (stability)
- coverage of thinking skills and processes (substantive evidence)
- cost, efficiency and practicality features
- generalisability for different types of applicant and under
different conditions
- value of intended and unintended consequences (consequential evidence)
may in principle be appropriate within a competency-based approach to
assessment.
The next step was to develop an interview schedule to explore perceptions
of assessment as they presently existed within the two groups being studied.
The interview schedule was designed to be carried out in stages, and in
association with a consideration of the actual assessment procedures and
instruments used in each organisation. The interview schedule focussed
on gathering information related to the current use of evidence of the
eight types identified by Nitko.
For example, in dealing with the first kind of evidence, the following
questions were asked. Do the assessments used in your company/organisation
cover all or only some of the content of your training program? Can you
say with confidence that your assessments consistently reflect work practice?
Do you think any additional assessment is necessary? (If so, what would
this be?) Could any assessments or parts of assessment be omitted? Does
the emphasis or balance in the assessment match the emphasis on the job?
Is the assessment up to date? Are the assessment tasks worthwhile
in themselves? (For example, do they contribute to learning?)
That these questions are not Dorothy Dixers (which would make
the exercise useless) is demonstrated by the fact that only the last of
these six questions led to the same answer in all six case studies.
A table sets out the details of each case study in summary, organised
in terms of the eight types of validity evidence.
The study showed that the eight types of evidence suggested by Nitko
were, with a single exception, regarded as important by the participants.
The exception, consequential evidence, relates, in part, to the
impact of assessment on third parties and would therefore
be expected to be less apparent to the organisations being studied.
Based on the information gathered in the case studies, a short self-administered
questionnaire with supporting advice has been prepared for assessors,
and appears
as appendix A in the report. This diagnostic tool includes practical
illustrations that emphasise the importance of the various kinds of validity
evidence.
The study presents firm evidence that the approach to validity indicated
by Nitko can be fruitful in improving competency-based assessment. The
report shows that competency-based assessment is not self-validating,
and that this is already recognised by industry.
Several other findings are reported:
- There was evidence that some practitioners were reluctant to allow
any scrutiny of their assessment practices. Although this was limited
in extent, it was nevertheless a cause for concern.
- Because this study required consideration of assessment records kept
by participants, it was notable that in some cases, the storage of records
and access to them were not well-developed, to the extent that the capacity
of the records to be audited was in doubt.
- Participants used ideas of recognition of prior learning
and recognition of current competencies in various ways,
indicating that there was no uniform understanding of this area.
- The use of integrated competency assessment (holistic
assessment), while valuable, appeared to raise some issues regarding
validity that have yet to be resolved.
- While the issue of grading arose in the course of the study, its role
is complex and issues of validity would vary depending upon use.
One influence on employment and on-job success that also has an impact
on validity could not be considered in the study because it appears to
be an unstated factor. This is the matter of attitude. In some cases this
may be a major factor, and its absence from consideration in training
packages is a cause for concern. This was beyond the scope of the present
research, but it did place some limitations upon the results produced
by this study.
The study has been able to demonstrate that, within the industrial areas
studied, the proposed expanded approaches to validity are already generally
regarded as important. The use of the broader notion of validity would
allow a clearer understanding of practical issues. A diagnostic tool has
been developed that will facilitate the development of such understanding.
Finally, as a consequence of this broader approach, a revised definition
of validity is proposed that sees it as the extent to which the interpretation
and use of an assessment outcome can be supported by evidence.
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