Drug testing is often an important part of hiring new employees. It helps to weed out people who can be a potential risk for the company. As well as to discard those who could cause accidents. There are several different types of drug tests available. Which test a company uses depends on whether it wants to test for the most commonly used drugs or less common ones as well. When it comes to drug testing, some companies may worry that the results are incorrect. The bottom line is that there is potential for error but the chances for this can vary. 

False Positive Drug Tests

In some cases, an individual may test positive for certain substances when they have not actually used them. This is known as a false positive. False positive drug tests can arise for a few different reasons. Lower-end drug tests can be faulty but in most cases, a false positive result comes from something that a person ate or drank. Several types of foods contain trace amounts of chemicals similar to those in certain drugs, which can cause them to test positive. For instance, poppy seeds can test positive for opioids, weight loss pills can test positive for amphetamines, and antibiotics can show up as opiates on certain tests. These are just a few examples that could lead to a false positive. 

False Negative Drug Tests

False negatives are typically less likely to occur than false positives but are still possible. Tampering can cause a false negative, especially when using a urine test. People can alter the test by diluting, replacing, or enhancing the sample to cover up what may be in it. 

It is also possible for a false negative to come as a result of extremely high cut-off levels. Essentially, what this means is that the threshold to indicate a positive is too high. A person may actually have substances in their system, but the amount does not reach the high cut-off of the test or laboratory, so they end up testing negative. This is something that needs to be closely monitored and mitigated while delivering the test. Unfortunately, some standard tests may not detect Oxycodone, a commonly used and abused drug. 

Rates of Inaccurate Drug Test Results

The exact number of inaccurate tests is difficult to know, as many may go unnoticed. Dwight Smith, MD, of the VA Medical Center in Black Hills, South Dakota, along with his colleagues at Boston Medical Center reviewed scientific articles on drug screening that spanned nearly 30 years. According to this research, false positive drug tests result in around 5 to 10% of cases. The numbers for false negatives are much harder to determine because as mentioned above, many tamperings go unnoticed. 

Looking for a Reliable Drug Testing Service for Prospective Employees?

Are you looking for a way to reliably drug test people applying at your company? We can help! Soteria Screening Laboratories offers several different types of drug tests and we can help you choose one that meets your company’s needs. We have helped in creating drug-free workplaces since our formation in 2001 and would like to do the same for your company. Give us a call today at 202-679-6670 with any questions that you may have. 

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