So, which is best: RPE or RIR? Ideally, using both scales in combination (like the above diagram) is the most sensible ...

A pain scale is a tool that doctors use to help assess a person’s pain. A person usually self-reports their pain using a specially designed scale, sometimes with the help of a doctor ...

While it’s mostly used as a reference tool (and, as noted above, is not the most objective measure of heat), you may turn to the Scoville scale when you’re using chiles in a recipe.