But they are ideal for certain situations.
Whether they be drug tests or medical tests, and instant test (aka “rapid” test), is what is called a “screen.” It’s a quick, down-and-dirty check. If you pass, it’s accepted. If you don’t, it needs further testing in a lab.
Of course, if it were that simple, everyone would be doing it, right?
Medical tests
On the medical side, there are instant tests for pregnancy, strep throat and HIV. All are very common. In my experience, if one of my kids passes the strep test, the doc sends it to the lab anyway. In our clinic, anyone who has taken and passed the instant HIV test wants the lab test too. So we send it. We’ve never had a negative rapid HIV test reversed in the lab.
My assumption is that if a home pregnancy test turns out negative (=NOT pregnant), the woman is not going to confirm that with a lab test. But you can bet she WILL if it’s positive!
Drug tests
Drug tests are similar. And different.
The similarity is that if you get a positive on the instant test, it goes to the lab for confirmation. Interestingly, we have had a few that were “hot” on the instant test, but the lab test came back negative.
Employers: Be advised that acting on the result of a positive rapid test can be a huge liability.
Instant drug tests are either urine or saliva. Like a pregnancy test, it’s a matter of whether or not a line appears on the testing device. No line: it goes to the lab.
Instant saliva tests (technically “oral fluid”) have a very short detection window. It can be from minutes on the short end up to (maybe) 48 hours for some drugs. For marijuana, 12 hours would be a stretch. They are a good, quick screen for total knuckleheads or for suspicion. For any other use, you would have to assess your particular risk.
Oral fluid lab tests, however, are much more reliable. The detection window is shorter than urine, but the positive rates are comparable to urine. What is lost in time span is made up for in “uncheatability” and convenience.
Instant urine tests provide a longer window of detection and fast results. For non-DOT testing, this can be a really practical method for employers. (DOT does not permit instant tests.)
Negative results are reliable and provided the same day. Non-negative results are confirmed in a lab test, for protection of donor, employer and drug tester.
Instant tests are not for every company. But same-day results are valuable for many. If you’d like to know more, call InOut Labs for info. We’re at 847-657-7900.
