Aa
false positive
Hi. I know that a few years ago some clinics stopped using the rapid HIV tests with oral fluid because they yielded a high amount of false positive results. Do the rapid tests that use blood also give a high amount of false positives? I want to get tested one last time for final peace of mind so I can finally move on from this. But I don't want to take a test that has a significant likelihood of yielding a false positive, so should I just get the conventional blood test done? Thanks.
ENOUGH IS ENOUGH ! ! !
ACCEPT YOUR 6 MONTH NEGATIVE TEST RESULT AND MOVE ON.
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ACCEPT YOUR 6 MONTH NEGATIVE TEST RESULT AND MOVE ON.
* Anyone who continues to post excessively, questioning a conclusively negative result or no-risk situation, will be subject to action by MedHelp. Conclusively negative results or a no-risk situation will be based upon the criteria established by MedHelp’s doctors. Action will be taken as follows:
* After excessive posting, a warning will be issued by MedHelp
* Continuing to post regarding the negative result / no risk situation will result in a 3 day suspension
* Continuing to post upon your return will result in a permanent ban.
All Rapid tests are FDA approved and are reliable when done at 3 months post exposure. You don't get false negatives at 3 months post exposure and those that get positive results still have to be confirmed.
As suggested by the article I sent it's at least not all rapid blood tests that has the problem - the Abbott Determine HIV test had fewer false positives than a regular blood test.
However, I've heard about the problems with the oral test - both false positives and false negatives. Some problems were linked to specific batches or batches that had expired. Other cases were related to incorrect use. I personally would go for a blood test. For people who are nervous I think the pain of a little pin prick is the least of their concerns when testing for HIV :)
The question of rapid vs. regular depends a bit on temperament and if you are able to 'handle' the waiting time with the regular test. Personally I haven't found this waiting time worse than, say, the waiting in the window period. In fact, in the waiting time after the blood was drawn I was more able to think 'OK, now I've done the right thing by testing and it will be what it will be'.
A nurse told me, and I think that is true for me too, that some people are uncomfortable with the rapid blood tests because the whole process is too fast! Just the mere thought of walking in from the street and coming out with a positive (or at least preliminary positive) results 20 min. later is scary. For them, the more drawn out process for the regular test, with an initial consultation on their risk, getting the blood drawn, then waiting a few days and coming in to get the result, gives time to consider the actual risk and to mentally prepare to get the result.
However, I've heard about the problems with the oral test - both false positives and false negatives. Some problems were linked to specific batches or batches that had expired. Other cases were related to incorrect use. I personally would go for a blood test. For people who are nervous I think the pain of a little pin prick is the least of their concerns when testing for HIV :)
The question of rapid vs. regular depends a bit on temperament and if you are able to 'handle' the waiting time with the regular test. Personally I haven't found this waiting time worse than, say, the waiting in the window period. In fact, in the waiting time after the blood was drawn I was more able to think 'OK, now I've done the right thing by testing and it will be what it will be'.
A nurse told me, and I think that is true for me too, that some people are uncomfortable with the rapid blood tests because the whole process is too fast! Just the mere thought of walking in from the street and coming out with a positive (or at least preliminary positive) results 20 min. later is scary. For them, the more drawn out process for the regular test, with an initial consultation on their risk, getting the blood drawn, then waiting a few days and coming in to get the result, gives time to consider the actual risk and to mentally prepare to get the result.
Just test. We are here for risk assestment not to research and tell you which antibody test is best for you.
Ok so- I've researched A LOT on this. I've read many, many articles stating that the rapid tests that use oral fluid tend to yield a high rate of false positive results when compared to blood tests. I haven't read anywhere about the rapid blood tests causing false positives. I know that any positive with a rapid test (or regular) is preliminary and has to be backed up with further blood testing.
So, is it ONLY the rapid oral fluid tests that tend to have higher rates of false positives? Or is it also the rapid blood test?
So, is it ONLY the rapid oral fluid tests that tend to have higher rates of false positives? Or is it also the rapid blood test?
Personally I would - assuming the lab uses the algorithm I descried - prefer a regular blood test (assuming the lab uses the algorithm I described, running WB on a eliza-reactive sample prior to giving a result back). While you get some extra waiting time, the result you get has at least been through WB, eliminating many false positives (there will still be another round of testing on a fresh blood sample, as described in case of WB positive).
However, I think other countries/labs may use different algorithms and will report an eliza result straight back and then run WB only on a newly drawn sample (at least I've seen posts to that effect).
However, I think other countries/labs may use different algorithms and will report an eliza result straight back and then run WB only on a newly drawn sample (at least I've seen posts to that effect).
All first test positives are given as preliminary positive results and any clinic or doctor office explains that to the patient before giving the test. That's why they have post testing discussions for further discussions.
Yes, that's what I'm saying. The difference between the testing types lies in the fact that in the case of the Rapid test the patient will of course know the result of the first test while it is being followed up by WB, whereas in the case of the lab blood test, the lab may run it through WB before giving any result to the patient (this is what happens here in Denmark). If the WB is negative, the result given to the patient is negative. Hence many false-positives are ruled out before the patient gets the result.
All positive tests have to be confirmed with a confirmative test. There is no exception.
Both rapid blood tests and regular eliza HIV blood tests can rarely cause false positive. For either tests, these false positives are eventually found out through follow-up analysis.
I've been researching if rapid blood tests are more likely to do it than their non-rapid counterparts. Certain information I found in official documentation seemed to imply the risk was higher with rapid tests.
However, at least for the one study I could find (examining the Abbott Determine HIV test) this wasn't the case. In this study they tested 1160 patients with both a rapid test and a regular ELIZA blood test. In 11 cases they disagreed on the results. Of these, 6 represented false positives on the part of the blood test. In other 4 cases, it was a false-positive from the rapid test. The final 1 case represented a false negative on the part of the rapid test.
http://jcm.asm.org/cgi/reprint/41/8/3868.pdf
So at least for this test it had actually fewer false positives.
There might be some truth to a higher risk of false positives rapid tests, however. In many labs, if you get a regular blood test and they find it reactive, they will run it through other tests (perhaps first an eliza test from a different manufacturer and then a Western Blott test). This will happen before the patient will even hear what the result is. Hence, most of the false positives are eliminated before the patient gets the result. Note that if the result is positive, a new blood sample will typically be drawn from the patient. This is to ensure against the rare case that a blood sample has been swapped with that of another patient or in case the original sample was contaminated etc.
I've been researching if rapid blood tests are more likely to do it than their non-rapid counterparts. Certain information I found in official documentation seemed to imply the risk was higher with rapid tests.
However, at least for the one study I could find (examining the Abbott Determine HIV test) this wasn't the case. In this study they tested 1160 patients with both a rapid test and a regular ELIZA blood test. In 11 cases they disagreed on the results. Of these, 6 represented false positives on the part of the blood test. In other 4 cases, it was a false-positive from the rapid test. The final 1 case represented a false negative on the part of the rapid test.
http://jcm.asm.org/cgi/reprint/41/8/3868.pdf
So at least for this test it had actually fewer false positives.
There might be some truth to a higher risk of false positives rapid tests, however. In many labs, if you get a regular blood test and they find it reactive, they will run it through other tests (perhaps first an eliza test from a different manufacturer and then a Western Blott test). This will happen before the patient will even hear what the result is. Hence, most of the false positives are eliminated before the patient gets the result. Note that if the result is positive, a new blood sample will typically be drawn from the patient. This is to ensure against the rare case that a blood sample has been swapped with that of another patient or in case the original sample was contaminated etc.
Thank you both. What about the Home Access kit? As long as I am sure to buy the one that is FDA approved and not one of these scammer kits then it is just as accurate?
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