English to French Medical Medical: Health Care Clinical trial/Medical treatment/Dosage/prescription

Please help me translate "aN" into French. I don't actually know what it stands for, as it is the first example in the text.

It relates to a table explaining what kind of activity/test to carry out on the patient. It states that the Glasgow Coma Score should be taken "weekly if aN at screening". This is probably not a typo because it occurs several times in the text.

Is this enough to help you give me an idea of what "aN" stands for?

I looked through the Glasgow Coma Score, there's nothing of the sort. I'm afraid I can't really give out more information.

thank you!
Virginie