The pain scale is a subjective measure in which the person is asked about the pain level. The objective measurement of pain tries to quantify the pain objectively. Primarily to assess the pain level of injuries and chronic patients. To this day, to the best of my knowledge, there is no objective measure of pain. The subjective perception of pests has a relatively high variance.
1 The Density of the sensory nerves (nociceptors) differs in different areas of the body. The head area, palms, hands, genitals, and nipples are rich in sensory nerves, so they tend to hurt more.
Major organs like the brain and the liver are not pain-sensitive.
2 Cumulative tissue damage = Result of multiplication of the affected tissue damage volume multiplied by the duration of exposure to the harmful agent.
The intensity of tissue damage volume.
Duration of exposure to the harmful agent.
3 The Regeneration rate of the damaged tissue is directly proportional to the speed at which the pain passes. For example, skin cells recover quickly, so the pain passes relatively quickly when we cut ourselves superficially with a knife.
It is relatively easy to produce a statistical estimate of objective pain, but the patient's subjective response to pain is more important than the intensity of the objective pain!
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