error would be extremely small because every measure is taken to assure these things don't happen. Can it happen? Yes. Has it happened? Yes. However, this occurs extremely rarely. To answer your 2nd question, I believe it would depend on the type of test and type of error to yield an inconclusive result.
There really wouldn't be a risk for human error on a rapid test as they are extremely easy to perform. If you got a negative at 5 months then you are negative. No if, ands or buts about it. A 5 month test is more than conclusive. 6 months is for people who already have compromised immune systems (cancer, being on chemo etc...) For you, it's time to celebrate...safely though!
Those test are SUPER SENSITIVE. The only human error you could really encounter would be:
1) Testing advisor not waiting 20 ~ 40 minutes to read the result
2) The advisor not cleaning your finger with the alcohol pad
3) Contaminating the testing swab pad my vigorously rubbing it between his/her fingers
The odds are in you favor always when it comes to rapid tests. Let me give you an example, I had a 3 year Oraquick Test and was told by numerous doctors and even the testing clinic that I didn't require a secondary test. Yesterday I went in for a second test, why? Well, according to these test, they are so accurate, when you test negative, you're negative, so why not test again, you have a 99.9% (almost 100% specifity in the oraquick blood sample test).
Anyhow, do yourself a favor, go get re-tested and explain your concern with the advisor. In my case I figured the girl who tested me wouldn't be "able to see a faint additional line" in my test due to adequate lighting...what did I find out yesterday?
Well, first, they use a special advanced light just for reading test strips to accurately evaluate the strip. Second, there is another specialist in addition to the counselor who admin's the test, both are fully trained to read and interpret and give results. Third, it was my luck yesterday that there was an HIV specialist in the office (Graduate Med Student) as well as a representative from ORASURE (mfg. of oraquick) doing quality control tests. Pretty much after testing again, awaiting my results, I sat in the waiting room with confidence. What happened? Negative....
Go get tested again, trust me. If you're truly negative, what do you have to worry about? I mean, it's just reassurance, that's all. Go get it done. Again, the chances of human error are so remote, these tests are fool proof, with that said, just go get another test, you'll feel confident.
Besides, remember, you're not being tested just to get a negative and take off. No no no, sometimes the unplanned happens, say I get my current GF pregnant...The last thing I want to worry about is my child becoming sick due to careless testing and care. I mean, you're being tested for your own health and well being, yes it eases the mind when it comes to fear and anxiety, but *knock on wood*, if you were infected, fear and anxiety aren't going to make you live any longer, you need to get tested up to 1 year, just for the sake of it. That's just my opinion. No one has to agree with me. But I like to be EXTRA sure. To the point where if an ad on the radio comes on saying "HIV this, HIV that, get tested", I used to change the radio station right away, but now, what do I have to worry about?? Confront your fear right in the face, get tested as many times as you want, it's to your ADVANTAGE. Some people can live with a 3 month test, a 6 month test, a 3 year test, when people ask what's the recommended testing period, people should say 3 months by the CDC, and 6 months by many clinics and doctors and anytime after that to your preference. People need to leave this choice up to YOU and just say "Hey, 3 months is min, after that it's up to you, up until you feel comfortable with your results"
In case of Antibody/Antigen testing what are the possibilities of human error?
I have tested 5 times and they all came negative.
The test is not done in the town i live, but it has to fly to Brisbane (about 2 hours) and get tested in the lab there.
There is a possibility that the samples are not correctly treated during transportation?
I have found that the decreased percentage of Lymphocytes in WBC is a sign of HIV infection.
My Lymphocytes decreased from 28% (that i always had in my life) to 25% in the last month.
That's also another reason i have to retest again.
Believe me, i don't like be in this situation and i don't feel to be paranoid. If i wouldn't have any symptoms i would be happy to forget everything and move on.