What is the difference between pain threshold and pain tolerance?
Pain threshold refers to the lowest intensity at which a given stimulus (mechanical, thermal) is perceived as painful; it is relatively constant across subjects for a given stimulus. Similarly, barring disease states, mechanical pressure produces pain at approximately the same amount of pressure across subjects. Specific devices have been developed to specifically measure thermal and mechanical pain thresholds, for example.
In contrast, pain tolerance is the greatest level of pain that a person is able to endure. Tolerance varies much more widely across individuals and depends on a variety of medical and nonmedical factors. Clinically, pain tolerance is of much more importance than pain threshold.