Several basic principles of epidemiology

There are four basic principles in epidemiology, including controllability, randomness, blindness and repeatability.

Statement of principles:

Control principle, experimental epidemiological research must set up a control, the purpose of setting up a control is to compare, which requires that the two groups of research objects must be comparable.

According to the principle of randomness, the participants in the experimental research must be randomly assigned to the experimental group or the control group, that is, the chances of participants entering the experimental group or the control group are equal.

Blind method principle, in order to avoid this bias, blind method can be used in the design, which makes the researchers unclear about the distribution of intervention measures and the research results are more real and reliable.

The principle of repetition ensures a certain sample size and makes the results representative.

Epidemiological concept:

Epidemiology is a science that studies the distribution and determinants of diseases and health status in a specific population, and studies the strategies and measures to prevent diseases and promote health. It is an important part and foundation of preventive medicine.

Main tasks:

The research scope of epidemiology is not only to study specific measures to prevent and control diseases, but also to study effective countermeasures to prevent and control diseases. The research object is the population, including all kinds of patients and healthy people.

Research scope:

1, the distribution of diseases and the reasons that affect the distribution.

To study the incidence, morbidity or mortality of a disease in different areas, at different times and among different people. Because of the difference in the number of some diseases in different time, different regions and different people, it is suggested that the distribution of pathogenic factors is different, and the reasons that affect the distribution are further sought.

2. Study the epidemic factors and causes of diseases.

The etiology or epidemic factors of many diseases are still unclear, and epidemiology should explore the factors that contribute to the onset and epidemic factors.

3. Natural history of disease

The whole process of disease from occurrence, development to prognosis can be divided into prodrome stage, clinical symptoms and signs stage and disease prognosis stage.

The natural course of different diseases is different, and some diseases have shorter natural course, such as acute bacterial infectious diseases, which generally progress faster. If active and effective treatment is not given, it will often cause adverse consequences. However, some diseases have a long natural history, so it is of great significance to study the natural history of diseases for the study and evaluation of prognosis.