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WHAT IS CROSS REACTIVITY, SENSITIVITY, AND SPECIFICITY?

The drug screens used by Halux Diagnostic are able to detect drugs of specific classes with a high degree of reliability. Still the possibility for cross reactivity to occur is unavoidable. Substances on a reacted immunoassay fall into two categories; the targeted drug class which are expected to be detected as a positive reading and structurally similar but unrelated substances that can bring a false positive. When the results are disputed and more information about the results are needed then confirmation testing is done. Confirmation testing is generally done by a registered lab with GCMS testing equipment. GCMS testing allows for a greater level of sensitivity and specificity. This testing allows the true positives to be separated from the false positives.

Cross Reactivity– A unrelated structurally similar substance detected that triggers a false positive.

Sensitivity- Measure of how often a test is able to correctly identify the substance within the sample as a true positive. The more sensitive a test the lower cutoff levels they possess allowing them to detect minute amounts of the tested substance. Low levels of sensitivity will produce more false negative results.

Specificity- Measure of how accurate a test is at distinguishing between a true positive and a false positive reading. Low levels of specificity will produce more false positive results.