How to investigate the feedback about the false results

Case Description:

On Sep. 24, 2019, we received a feedback from one of our distributors: one user in a clinical lab tested a blood specimen for HBsAg infection with our Accu-Tell® HBsAg Rapid Test Cassette and the other brand rapid HBsAg test. ccu-Tell® HBsAg Rapid Test Cassette showed negative results while the other brand showed positive results. The user doubted if this lot of Accu-Tell® HBsAg Rapid Test Cassette gave the false results.

Our Action and Solution:

AccuBioTech technical team started the investigation once we received the above feedback:

1. We checked theof the same lot, which did not show any false results;

2. We evaluated the retained product samples of the same lot and all the retained product samples gave the proper results;

At the same time, we asked the user to do the following:

1. Please confirm if the blood specimen is positive or negative by other diagnostic method such as Elisa Test Kit instead of by other brand rapid test;

2. Please give us the brand name and lot number of the comparison rapid test so that we can perform the comparison evaluation in our labs;

3. Please give us the results pictures for detailed study;

4. Please confirm if the user perform our tests and read the results strictly according to our product insert.

Investigation Results:

On Sep. 30, 2019, we received investigation results from our distributor: the user tested the same blood specimen by Elisa Test and confirmed the specimen was negative, which proved that Accu-Tell® HBsAg Rapid Test Cassette gave the CORRECT test results but the other brand rapid test gave the false positive results.