Yes, although excessive values (the exact threshold for concern is debatable) are a cause for concern.
Just like PSA, really
Surely the whole point is to spot trends, and in that regard absolute values aren't critically important
Update:
Both companies commented, each saying they don't know anything about the calibration procedures the other one uses.
The last oil sample was taken in duplicate. Normally I do this in case it gets lost in the mail to the USA.
This time, one was sent to Avlab (my usual firm) and one was sent to Blackstone.
Avlab:
Blackstone
Both were taken within seconds of each other, from a warm engine (just after a flight), and having waited for 1 minute from opening the oil drain.
I have asked both firms to comment.