ABSTRACT
This chapter presents the results of studies of the epidemiology of pain using classical epidemiological methods. It describes the basic principles of epidemiology; and introduces the concepts and approaches for exploring the molecular epidemiology of pain. Epidemiology provides a framework for determining the prevalence, incidence, and risk of pain in populations. The new molecular epidemiology paradigm integrates the use of biological markers that indicate events at the physiological, cellular, and molecular levels. In the United States alone, lost productive time resulting from common pain conditions among active workers costs an estimated $61.2 billion annually. Studies of the incidence, prevalence, severity, and treatment of pain have a number of shortcomings. Epidemiologists typically identify two major types of study designs: experimental and observational. Epidemiologists often perform case–control studies because they are relatively easy to conduct. The control population should be comparable with the case population in terms of socioeconomic status and other unmeasured factors.
