Drug Screen vs Drug Confirmation

Even for the provider who has been testing for years, ordering and interpreting drug tests along with knowing insurance companies drug testing policies can prove challenging.

The differences between a qualitative test (drug screen) versus a quantitative test (drug confirmation) remains universally misunderstood. Qualitative tests are immunoassay tests correctly called a drug screen. Using antibodies to detect the presence of selected drugs and/or their metabolites, a drug screen is the most common and most used type of drug testing. It is also the test that produces the most false positive and false negative findings. A cup test, drug testing strips, a table top analyzer or a large analyzer within a lab all perform qualitative drug tests (drug screen). The class of drug a patient is taking is what a drug screen detects.

Quantitative tests, commonly known as drug confirmation tests are done using gas or liquid chromatography within a lab. This more expensive, high complexity test, is highly accurate. Quantitative tests determine the exact drug along with metabolites the patient has in their urine.

Drug Screen = Shows which class of drug(s) a patient is taking.

Drug Confirmation = Shows exact drug(s), metabolites, and levels of both.

In the world of drug testing today, insurance companies, including Medicare and Medicaid, want the patient to have a drug screen done. Based upon the results of that screen, they will allow you to reflex for confirmation. Gone are the days where one box is checked and every drug known to man is confirmed. Prescribed medications and any inconsistent findings on the drug screen are allowed and expected to be confirmed. What about drugs that cannot be screened, you ask. You did ask that, correct?

This is a great segue to every provider’s favorite subject: Documentation. We do not make the rules and all of you know about not shooting the messenger, however, since the insurance companies tend to control the healthcare purse strings, we have to abide by them. The provider can order additional drugs not able to be screened, and should based upon good medicine and the best interest of their patient, but must document in their notes why they would like that patient’s sample tested for that drug.

Gabapentin comes to mind. There is not a screening test for Gabapentin. In some regions it is abused. If a patient is not prescribed Gabapentin, but the provider has a legitimate reason their patient may be abusing this drug, they should order it to be confirmed with the appropriate documentation.  

Medical decision making is what every provider does on a daily basis. When a toxicology report comes back. a medical decision is presumably made based on that report. What was positive or negative on the report? Were the results expected or not? Most importantly – What was done based on the report? Once again, all of this has to be documented. As we all know, the better we document the less we get hassled by the insurance companies.

Industry Lab is here to help providers interpret results, answer any questions regarding the testing, and provide knowledge regarding the different insurance drug testing policies. Our job is to produce top-notch testing with quick turn-around so the provider can continue to do what they do best. Serve their patients.    

Lance Benedict

President/CEO Industry Lab Diagnostic Partners