Determinants are factors or events that are capable of bringing about a change in health. Some examples are specific biologic agents like bacteria that are associated with infectious diseases or chemical agents that may act as carcinogens. Other potential determinants for changes in health may include less specific factors, such as stress or adverse lifestyle patterns (lack of exercise or a diet high in saturated fats).
b. Distribution
In epidemiology, the frequency and pattern of health-related characteristics and events in a population. In statistics, the observed or theoretical frequency of values of a variable.

c. Morbidity and mortality
Two terms central to epidemiology are morbidity and mortality. The former, morbidity, designates illness,