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A recent symposium held in Atlanta and sponsored by the Centers for Disease
Control and Prevention, the College of American Pathologists, and the
Cytopathology Education Consortium (American Society for Cytotechnology,
American Society of Clinical Pathologists, and American Society of Cytology)
looked broadly at issues related to cytology proficiency testing (PT). The subject was examined thoroughly-from the
historical perspective, through currently used techniques for PT and
quality assurance, to an exciting look at the future with its evolving new
technology. The symposium presentations are published in this issue of
Laboratory Medicine and provide a useful reference for this important and
timely subject. Summary discussions of each symposium section follow this
editorial. While the stimulus for the scientific meeting came from the
frustrating, unsuccessful effort to launch a national cytology PT program,
benefits from the deliberations reach far beyond the federal regulatory
needs.
The inability to implement a national cytology PT program as mandated
by the Clinical Laboratory Improvement Amendments of 1988 (CLIA) has
required us to reexamine all possible alternatives. This
"rethink" affords opportunities to explore new and innovative
approaches to the way proficiency is measured in the cytology field-for
education, certification, or regulation
Background.
CLIA, as enacted by Congress, has had
far-reaching effects on laboratory medicine in the United States. CLIA in
particular has significantly affected the practice of cytology. Some
sections of the law address cytology specifically. Among the requirements
are the establishment of personnel standards, workload limits and quality
control measures, and individual successful participation in a cytology PT
program.
Implementation of a cytology PT program on a national scale has proven
to be a difficult task, even though smaller programs are in operation. New
York State has carried out state regulatory cytology PT for 25 years, and
Maryland established a program in 1990. In addition, New York City has
conducted regulatory cytology PT for approximately 14 years. During the
process of developing regulations to implement the CLIA requirement for
cytology PT, the responsible federal agencies relied heavily on experience
from these programs to establish a national model.
The regulations for CLIA-mandated cytology PT outline a program to be
conducted on- site, using carefully referenced glass slides. One
difficulty in implementing this program is collecting the requisite number
of high-quality glass slides representing the appropriate diagnostic
categories. The cost of collecting and referencing the glass slides is
very high, and legal and logistical barriers to collection exist as well.
Given these constraints, the time needed to assemble and reference a
sufficient number of slides for a national program would be considerable.
For these reasons, it has proven to be an impossible task to collect and
reference sufficient glass slides to conduct PT on a national scale.
Of the many insights and ideas that were discussed during the
symposium, the following stand out in my mind:
Evaluation.
Although the value of PT as an educational
tool is widely recognized, we do not know the extent to which PT measures
true performance. The implementation of national programs will allow us to
evaluate the effectiveness of this tool, and it will be important to
design and conduct studies to carry out this evaluation.
Source of screening errors.
A PT program that
accurately reflects work performance needs to evaluate both functions of
cytology testing: screening or location (the scanning of slides to find
abnormal cells), and interpretation (identification of abnormal cells).
While it is relatively easy to design an examination that tests
interpretive skills, it is much more difficult to detect problems in
locating abnormal cells. Inadequate locator functions primarily are
produced by too great a workload and, consequently, insufficient time to
examine a given slide; distractions or failure to concentrate; and poor
screening techniques. CLIA regulations for workload limits and quality
assurance have addressed the first problem. Cytology PT can test screening
techniques. It is questionable, however, whether one can test for
distractibility using cytology PT because normal working conditions can
not be duplicated exactly.
Use of facsimiles.
Examinations to test for
interpretive skills can be rapidly designed and implemented. Professional
organizations and universities currently are using color transparencies or
computer-reproduced images, at relatively low cost and with excellent
standardization. At present, however, examinations using traditional glass
slides are the only means available for testing locator skills.
The future.
An area of great promise appears to be
digitized computer imaging. Several systems for producing computer images
of cells from cytology slides have been developed. Computers can simulate
the actual scanning of slides. Development of a cytology PT system using
this technology would offer the considerable advantages of standardized
tests; the measurement of both locator and interpretive skills; and
elimination of glass slides as the test medium, resulting in considerable
cost savings.
Multiple approaches.
The idea of developing a variety
of cytology PT programs for meeting CLIA implementation needs has
considerable merit. Multiple approaches explored for a period of years
will begin to yield data about what kinds of programs are most effective
and how well the programs reflect true performance.
Effective alternate approaches using facsimiles in lieu of glass slides
can be put in place fairly and quickly. In addition, there is need to
stimulate the development of digitized computer imaging. In my opinion,
this is the future of cytology PT.
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