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Is there a difference in accuracy and reliability of 4th generation duo tests

Dear Drs

Is there a difference in accuracy of the 4th generation duo tests. I.e. those conducted at a clinic and those sent to a lab.

  I had a 4th generation duo test at 28 days at a clinic in London (medicentre). Blood was taken from my arm and I received the result after a 20 minute wait.  Negative by the way

However I understand there are also these duo tests where the blood goes off to the lab and the result in received in a few hours....is there any difference in reliability and accuracy between the two?

And is 28 days conclusive?

Regards

Jeremy
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Avatar universal
Regards

Jeremy
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239123 tn?1267647614
MEDICAL PROFESSIONAL
The main take-home message from that link is that the oral fluids rapid tests take longer to become positive than both the rapid and lab-based blood tests.  We have made this point several times on this forum in the last few weeks.  Since you apparently had a blood test, this information doesn't change my opinion or advice.
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Avatar universal
Dr

The articles on this link
http://www.aidsmap.com/Accuracy/page/1323395/

Say that the point of care tests are less accurate than lab tests...and state some quite clear and not good stats as to the accuracy of even the 4th generation rapid duo tests. Not done in a lab.....this has worried me a lot...

What would be your comment on this?
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239123 tn?1267647614
MEDICAL PROFESSIONAL
Yes, obviously.
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Avatar universal
Given the above, that I can confirm I do not need further testing?
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239123 tn?1267647614
MEDICAL PROFESSIONAL
A half day makes no difference.  Don't worry about it.
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Avatar universal
Thank you for your reply...could I just clarify..in fact when I calculated when I took the test it was at 27.5 days rather than 28 days....does that make any difference to the conclusiveness ( if that is a word) of the result?

Rgds
Helpful - 0
239123 tn?1267647614
MEDICAL PROFESSIONAL
Welcome to the forum.

All the 4th generation HIV tests -- i.e. combination tests for both HIV antibody and p24 antigen -- have similar performance, whether lab-based or point-of-care (in-clinic) tests.  They are considered 100% reliable any time 28 days or more after the last potential HIV exposure.  Your negative result is reliable regardless of what specific test your clinic used.

Below is a link to a thread that discusses test performance at various intervals, including the reasons that many offiical agencies (especially in the United States) continue to recommend 3 month testing despite reliable results at different times.

http://www.medhelp.org/posts/show/1704700

Best regards--  HHH, MD
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