[johnfactorial]

Pain was once considered a fact of life, and vital signs were those 4 signs which can indicate a patient is alive: body temp, pulse, respiratory rate, and blood pressure.

Then the notion of pain as the "fifth vital sign," came about. Some argue we resultantly now have an opioid epidemic.

There is a fascinating NPR show episode on this topic: https://www.npr.org/programs/invisibilia/701219878/the-fifth....

Edit: another source of info: https://www.medpagetoday.com/publichealthpolicy/publichealth...