Epidemiological definition of risk. However, in epidemiology the definition of risk is purely one of probability or chance, as measured by the occurrence of new cases of disease in a defined population over a defined period: risk = number of (new) observed cases. number at risk (disease free) at the start.Click to see full answer. Also, what is a risk factor in epidemiology?In epidemiology, a risk factor is a variable associated with an increased risk of disease or infection. Determinant is often used as a synonym, due to a lack of harmonization across disciplines, in its more widely accepted scientific meaning.Also Know, what are the 3 types of risk factors? Types of risk factors Behavioural risk factors. Behavioural risk factors usually relate to ‘actions’ that the individual has chosen to take. Physiological risk factors. Demographic risk factors. Environmental risk factors. Genetic risk factors. Income. Age. Gender. In respect to this, what are the risk? Risk is the potential for uncontrolled loss of something of value. Risk can also be defined as the intentional interaction with uncertainty. Uncertainty is a potential, unpredictable, and uncontrollable outcome; risk is an aspect of action taken in spite of uncertainty.What is the meaning of risk factor? Medical Definition of Risk factor Risk factor: Something that increases a person’s chances of developing a disease. For example, cigarette smoking is a risk factor for lung cancer, and obesity is a risk factor for heart disease.