Table 1 Reference categories of pain intensity

Excruciating

Threshold of pain under which many people would choose to take their life rather than standing the pain. This is the case, for example, of severe burning events, which may make victims jump from buildings, or other conditions associated with suicidal attempts by sufferers (e.g., cluster headaches). Many forms of torture have been designed to inflict pain at this level. Behavioral patterns can include loud screaming, involuntary shaking and extreme restlessness

Disabling

Most forms of functioning or enjoyment are prevented as the direct result of pain. Symptoms are continuously distressing. Individuals affected often substantially reduce activity levels and refrain from moving. Pain at this level can disrupt or prevent sleeping. Only strong analgesia can relieve it

Hurtful

Pain experiences that most would consider disruptive of daily routine. Although not entirely preventing individuals from functioning, their ability to do so is impaired as the direct result of pain, and often accompanied by the desire to take painkillers or seek treatment. Frequent complaints are often present. The possibility to enjoy pleasant experiences is impaired, as is performance on mentally demanding tasks, alertness and attention to ongoing stimuli

Annoying

Pain experiences are not intense enough to disrupt the routine or daily activities of individuals, their possibility to enjoy pleasant (positive) experiences, or their ability to conduct mentally demanding tasks that require attention. Sufferers do not think about this sensation most of the time, and when they do they can adapt to it