Menopause and spotting 

Hi Invertzoo. ,
As stated “a woman who still has her uterus can be declared to be in post-menopause once she has gone 12 full months with no flow at all, not even any spotting.” I read everywhere that a woman must go 12 months without a period but I haven’t read about going 12 months even after spotting. 
1.Is there any research into this and could you direct me to articles?
2.I was wondering if perhaps after spotting the time to being declared post menopausal was less than 12 months? Thank you