Public Health Law Map - Beta 5 - Medical and Public Health Law Site

emoving the plantar wart.
This emphasis on diagnosis leads to laboratory diagnosis as the ideal of
technological medicine. [Fortess EE, Kapp MB. Medical uncertainty, diagnostic
testing, and legal liability. Law Med Health Care. 1985;13:213–218.] Clinical
laboratory tests are seen as objective, while taking a history and physical is
subjective. Laboratory tests are easy to replicate, may be discussed without
reference to the context of the specific patient, and, at least superficially, are easy
to interpret. Tests with numerical results lend an air of science to medical practice.
Before the advent of digital electronic calculators, calculations were worked out
with slide rules. When digital calculators became cheap enough for general use in
the classroom, many teachers opposed their use. There was a philosophical concern
with the false rigor that electronic calculators created. The slide rule was accurate
to only two or three digits; thus, using a slide rule constantly reminded the student
of the approximate nature of the underlying data. Digital calculators and digital
reading instruments display many digits—but most medical data are approximate,
usually to only two digits of accuracy and sometimes less. Manipulations of these
data that do not take into account their limited accuracy lead to spurious results, but
results that appear to be scientific because they are numerical.
This problem of false rigor is exacerbated by the use of multiple test panels. These
panels include large numbers of tests that measure mostly unrelated parameters.
The test results are expressed numerically, but the evaluation of the results depends
on the comparison of these numerical values with normal values. Normal values
are determined by statistical techniques. They are usually set such that 5% or 10%
of healthy people given the test will have values outside the normal range.
When a patient is given a panel with 20 independent tests, each with a normal
value defined by the 95th percentile, then the probability is high that at least one
test will be falsely normal or abnormal. The noise from the false test results makes
it more difficult to evaluate the diagnostic content of the test panel and increases
the chance that important information will be lost in the mass of data. The tests
may also document important problems that the physician missed. When an injured
patient seeks the advice of an attorney, the attorney has the luxury of working
backward from the injury. If the physician did not order the proper tests, then all
the other tests that were ordered become irrelevant. And if the proper test was
ordered but the results were overlooked or ignored, the emphasis on ordering tests
accentuates the error in not acting on the relevant test results.
c) Specialty Blinders
Many specialists believe that the best way to avoid litigation is to ignore all
problems that are not part of their specialty. But many patients have multispecialty
problems that require one physician to take overall responsibility for their care. This
problem is exacerbated if the specialist is at the end of a long referral chain. In this
situation, the specialist is prone to assume that someone else has ruled out all
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