There is insufficient information here: different labs/same method except MRD? Was the assay validated at lab 1 then transferred to lab 2? Or was the method developed/validated independently at the two labs? Are the labs supporting the same protocol or different? Same indication or different? What would be the purpose of combining titers-some sort of analysis of titer level impact?
The above information would help with any response. Absent that I would venture that with two different MRDs that the assays have different methods, though I'm guessing quite similar. With different MRDs the cut points will be different and thus even the relative quantitation from a titration could be different, making combining titers problematic. You could do a comparability experiment: exchange samples from both labs and see what you get. If the original titers are recovered then it would suggest combining might be ok.
Depending on whether you have sufficient "n" in both labs, you could simply run independent analyses and see if the pattern is similar between labs. The general observation is higher titers have greater impact, but the actual level of titer is usually not a good predictor of impact, I.e., same titer from different subject may have quite different impact.
Original Message:
Sent: 5/20/2025 7:15:00 AM
From: Anonymous Member
Subject: Pooling of ADA titer data from different labs
This message was posted by a user wishing to remain anonymous
Keen to understand the best practice when pooling ADA titer data from different labs with different MRD. Specifically, has the ratio of MRD been utilized for normalizing data from different labs?