My son had his B12 tested on 27th March and the reference range was given as 190 to 660 ng/L. Had it tested again on 1st June by the same lab and the reference range is now given as 180 to 999ng/L with a note saying 'Please note revised reference range from 31st May'.
What's going on? Has there been some directive to drop the lower level so that fewer people get diagnosed? Has the lab got a new machine?
Seems odd that the 'normal' level should be lowered at a time when it seems that the medical profession is finally becoming a little bit more aware of B12 deficiency.