The hazards of bedside Bayes
J. M. Harris Jr
Those who advocate the use of Bayesian or decision-analysis approaches to
solve clinical problems often assume that data on the sensitivities and
specificities of diagnostic tests are readily obtainable and reliable. For
the most part, however, there is little information currently available on
the sensitivities and specificities of common tests. A critical review of
the literature was performed for seven commonly used tests. This study
showed that there is significant variability among the reported results of
five of these tests. Such variability was not expected but is one more
factor that any quantitative approach must consider. Two tests, the
rapid-sequence excretory urogram and the thallous chloride TI 201 cardiac
stress test, did not, however, show significant variation among the
reported sensitivities and specificities. These findings have relevance to
clinicians attempting to diagnose disease, to advocates of quantitative
decision making, and to researchers seeking to clarify the nature and role
of diagnostic tests.
