Understanding Weapon/Armor Tooltips
I assume you are talking of combinations when comparing two armor pieces? If so, then certainly:
red number with white text means you have the same stat on your armor, but the red version is lower, in the comparing window you have there a green number with white text, meaning the same stat is higher.
Green number with green text means you do not have that stat on your current armor.
example:
armor 1
+2 power
+1 prec
armor 2
+3 power
+2 tough
armor one would be displayed as +2(red) power (white) and +1 (green) precision (green)