The gold standard for pain analysis currently relies on patients self-reporting how they feel, relying, in different places, on either a numerical scale (0 as no pain, 10 as worst pain), or a system of smiley faces.
"Step one in treating pain adequately is measuring it accurately and that's the challenge," says Carl Saab, who leads a pain research team at Cleveland Clinic in London. "Nowadays the standard of care is based on 'smiley faces' that riddle ER rooms." This system can be confusing for patients, he says, and especially problematic when treating children and non-communicative patients.