Introduction: Value of epidemiological research for clinical practice

Epidemiology is the scientific analysis of the occurrence of diseases in the general population in relationship to the characteristics of the individual subjects and their environment. Traditional epidemiology is concerned with discovering basic truths on the frequencies of diseases and their aetiology; clinical epidemiology represents a special field that translates clinical practice into quantitative science; public health epidemiology is the basis of knowledge, prevention and treatment of diseases in the population. Epidemiology has an important clinical impact for it can be used to understand the pathogenesis of diseases, improve diagnostic accuracy, help the patient to reduce risk factors and the physician to choose the correct therapeutic approach.