Checking Consistency among the Four Basic Indicators of Diagnostic Testing in Saudi Medical Journals

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Hamzah Abdul Majid Serag
Ali Muhammad Ali Rushdi


We provide a novel method for validating any purported set of the four most prominent indicators of diagnostic testing (Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value), by observing that these indicators constitute three rather than four independent quantities. This observation has virtually been unheard of in the open medical literature. We defined two functions, which serve as consistency criteria, since each of them checks consistency for any set of four numerical values claimed to be the four basic diagnostic indicators. Most of the data we came across in various Saudi medical journals met our criteria for consistency, but in a few cases, there were obvious unexplained blunders. We relate our present findings to the more general issue of detection and ramifications of unwelcome flawed data.

Diagnostic testing, sensitivity, specificity, positive predictive value, negative predictive value, consistency criterion, flawed data.

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How to Cite
Serag, H. A. M., & Rushdi, A. M. A. (2021). Checking Consistency among the Four Basic Indicators of Diagnostic Testing in Saudi Medical Journals. Asian Journal of Medical Principles and Clinical Practice, 4(1), 14-27. Retrieved from
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