Diagnostic Availability (DA) based on Pythagorean Theorem as a Novel Index for Integrative Evaluation of Diagnostic Tests
2017
Accurate diagnosis is the prerequisite for effective treatment of diseases. Various biostatistics indices have been
used to evaluate the performance of diagnostic tests. The distribution of test results commonly shows a relatively
fixed overlap between the diseased and non-diseased populations, and the two main properties of laboratory tests
sensitivity (Se) and specificity (Sp) usually demonstrate an inverse relationship of each other. An inverse relationship
is also seen in the two sides of a right triangle where the hypotenuse serves as an integrated functional index of the
two sides, as reflected in the geometric equation Pythagorean Theorem (PT). We have developed a novel test
performance index named diagnostic availability (DA) based on the theory of PT, which integrates and reflects the
combined efficiency of Se and Sp. When Se and Sp were changing inversely as seen in the vast majority of clinical
settings, DA was superior to the other indices diagnostic efficiency (DE), Youden index, and Kappa coefficient (К) in
reflecting the overall test performance of a test. It was also the only one responsive to the reciprocal changes of Se
and Sp. Therefore, we propose the additional consideration of DA besides Se and Sp during the determination of
the optimal test result cut-off point. In the rare scenarios that Se and Sp are changing in the same direction, DA, J
and К outperforms DE in reflecting test performance. Furthermore, DA can also help identify the better test when two
tests exhibit similar areas under the curve (AUC) in the receiver operating characteristic curve (ROC) analysis. In
conclusion, DA is a novel index for overall performance evaluation of diagnostic tests reflecting the combined
efficiency of Se and Sp. It shows superiority over other commonly used indices in the assessment of overall test
performance and serves as a valuable addition to the existing indices.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
21
References
0
Citations
NaN
KQI