Not being medically qualified, it is with some trepidation that I suggest something other than Eytan's answer but it seems clear to me that whoever has written this is writing Hebrew from English as language of reference and it clearly spells out "motive". I could suggest "purpose" as an alternative. I could not say what that means in medical terms. I will not be offended if you opt for Eytan's answer but I am not sure it is correct, hence this offering. What goes into Proz is used by others and I would not wish to see a translation that might be wrong propagated if I have question marks about it.