Other causes include: 1  A fall against a hard surface in the seated position, such as a fall from a horse. 2  A direct blow to the coccyx, such as in contact sports.  Straining or dislocating the coccyx. This can happen due to poor posture while driving, or repetitive injury from sports such as rowing or cycling.
1 Positive test results also can mean that the amount of a substance being tested for is higher or lower than normal. 2  A negative test result means that the substance or condition being tested for was not found. false-negative test result may suggest that a person does not have a disease or condition being tested for when he or she does have it. For example, a false-negative pregnancy test result would be one that does not detect the substance that confirms pregnancy, when the woman really is pregnant.
The cost of a drug test is the same whether it is positive and confirmed or negative. The employer is paying for a drug test. The protocol for a drug test is that they are subjected to an immunoassay screening (qualitative).If it passes, that's it. If it doesn't pass (non-negative), then it is forwarded to confirmation (GC/MS).ecs New Member. The cost of a drug test is the same whether it is positive and confirmed or negative. The employer is paying for a drug test. The protocol for a drug test is that they are subjected to an immunoassay screening (qualitative). If it passes, that's it.