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Designing XML based medical applications for windows
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The changes in the US medical scene have left in place legacy electronic
binary medical records systems that are unable to communicate with each other.
This paper examines how XML and Visual Basic can be used to build Windows
and intranet applications that enable these systems to communicate. Emphasis
is placed on an incremental deployment of these systems.
The widespread deployment of PC's running Windows means that any XML
based system should be deployed on these platforms. The predominance of VB
programmers, and the simplicity of using the MSXML ActiveX object dictate
the use of these systems.
Three case histories where this combination are used are examined.
The changing health care scene in the United States
The health care scene in the United States today is unrecognizable from
what it was 10 years ago. Cleveland, Ohio is typical example of how the scene
has changed.
Ten years ago the majority of medical practitioners were in private
or small group practice, operating out of community hospitals and referring
complex cases to tertiary care centers.
Medical records were for the most part paper based, parochial, and reflected
the whims of local providers. Communication between provider nodes in this
system was invariably done using 'referral letters'
Under the pressure of diminished reimbursement from insurance providers,
and pressure from the Federal Government, this system has imploded.
Today the original Tertiary care providers have reinvented themselves
as Hospital systems, and now employ or manage between them 90% of the Doctors,
and all the hospitals. They have also built several outpatient clinics to
service the local population.
These providers have attempted to impose a universal electronic records
based system on their satellites, but for the most part all they have succeeded
in doing is impose an additional layer of complexity on top of the old systems.
The reasons for this include
- 1. The pre-existence of proprietary binary electronic record systems.
- 2. The difficulty of converting paper to electronic systems.
- 3. The innate conservatism of medical practitioners.
- 4. The length of time necessary to deploy new systems.
- 5. High initial system costs which lock provider nodes to a single
vendor.
The promise of XML and VB
XML promises a means of providing flexible, incremental employment of
electronic systems, and also provides a means for easy communication between
disparate binary electronic systems.
The one thing all medical systems have in common is that they all (99%)
run Windows on PC's. Most of the medical programmers are versed in VB (80%+
use this language as their language of choice. Nation wide the proportion
of VB:Java programmers is approximately 10:1), Foxpro, or C++. It is thus
natural that any system deploying XML should leverage these existing conditions.
The existence of the MSXML and more recently the MSXML II ActiveX object's
make integration of XML and data bases an almost trivial exercise for the
VB programmer using Visual Studio.
Ultimately and ideally the whole record system will be based on a non-proprietary
mark-up language (XML), but till that day comes XML can still be useful and
used as an incremental replacement for existing systems. The following are
case histories demonstrate some of the current uses.
Case studies
Creation of and management of new records
PrimaHealth International is an organization concerned with the exchange
of medical information across International boundaries. Typically a potential
patient or their doctor will provide information of the patients medical condition,
and this information is then used to match the patient with a suitable treatment
center. Tenders and cost estimates for care are solicited from several participating
centers in several countries.
This process has recently been moved over from a traditional to a web/XML
based system. Typically the client will fill out an HTML based form which
is used to automatically generate an XML file. Triage personnel are automatically
advised (email) of the receipt of a new file, and can immediately evaluate
it. Reports can be forwarded to participating specialists, and in most cases
a treatment plan can be generated with in 24 hours of the receipt of the initial
information. Once approval of a treatment plan has been received from the
client tender documents are generated from the XML files, and quotes are usually
received within a week. Typically the only bottle neck tends to be getting
exit and entry visa's for the patient.
ASP and VB is used extensively throughout the whole process to access
and manipulate the XML files. This automation has allowed the whole process
to be reduced from several weeks to a few days.
As a further benefit PrimaHealth is able to get many of the tests carried
out in the clients locality, and indeed in many cases a costly trip overseas
has been prevented.
Tracking blood test results
With automation and centralization of blood analysis, the cost of actual
analysis has been reduced to a few cents rather than several dollars. However
the cost of processing, tracking, and documenting a test has continued to
climb, and now constitutes 95+% of the cost of the test.
Traditionally the following steps were employed in a simple blood test.
- 1. Patient visits doctor
- 2. Test is ordered (paperwork)
- 3. Patient goes to phlebotomy area (paperwork)
- 4. Blood is drawn and placed in container (paperwork)
- 5. Blood is sent to lab (paperwork)
- 6. Blood is analyzed, and result recorded (paperwork)
- 7. Result is sent to Doctors office (paperwork)
- 8. Result is triaged (human Intervention)
- 9. Patient visits Doctor for report.
In many cases the result had to be tracked down. This usually involved
sleuthing skills and several phone calls. A recent study showed the average
time taken to track down a delinquent record was about half an hour! Often
it appeared that the patient had never even gone for the test.
An XML/VB based system has simplified the system considerably. Now all
the paper work is automatically generated from the original order entry, and
an Intranet allows automatic tracking of the results. Further more simple
programs allow automatic triage of the result, communication between provider
nodes using different electronic systems, and in the many cases the follow
up visit can be aborted.
Using XML based patient record files as pointer files
Most proposals for paperless systems suggest moving all the patients
file over to a complete XML based system. This however does not take into
account the innate conservatism of medical practitioners, and under estimates
the amount of angst involved in the process.
A compromise system creates an XML based record that provides pointers
to existing records, and allows the practitioners to continue making hand
written notes etc. Further more the XML based system can point to other electronic
sources, and provide links and a pointer to a broker to allow interpretation
and presentation of these records. Letters stored in Word or WordPerfect are
a trivial example, X-ray records stored in a binary format are a slightly
more complex example.
With decreasing storage costs several centers are experimenting with
scanning hand written notes in Fax quality, and storing these for instant
access. Although OCR is advancing to the point where it can read ordinary
handwriting, it is doubtful it will ever be sophisticated enough to read doctors
handwriting!
Conclusions
There is no doubt that the universal acceptance of XML is a boon to
the dissemination of medical information. However implementation of XML based
systems runs into obstacles often of a political nature. Implementation to
be successful has to work with existing systems, and just as importantly has
to overcome the innate conservatism of the medical professions.
This paper shows how XML systems can be successfully implemented by
working with the existing Windows based systems already in place in most medical
institutions. this eases transition and reduces the angst of all involved.
Acknowledgements
The author would like to thank PrimaHealth International (http://www.primahealth.net)
for allowing him to use their applications and material in this paper.