As a home health and hospice nurse we use these pain scales along with a pain "thermometer" it starts with green at the bottom and progresses through to red, along the side it has the 0-10 scale to help us document the pain. I have also noted some ppl dont realize how much pain they are in until I can help them relieve some of it, they dont reconize what has become normal to them, but the facial expressions, restlessness, increased pulse and bp all are clues