Hey Marisa, I am no expert, I am a new grad RN. But, what I was taught is that only pitting edema is rated 1-4 based on depth of the indentation made in mm. So, +1 pitting would be 2mm indentation, +2 would be 4 mm indentation, +3 would be 6 mm indentation, and +4 would be 8 mm or more. As far as I know, non-pitting edema is not rated 1-4. Hope you find an answer to this from someone more experienced than I, otherwise, I would definitely discuss this further with your instructor! Best of luck to you.
