1. PRIMORDIAL PREVENTION – to inhibit the emergence of risk factors in populations in which they have not yet appeared. The risk factors are in the form of environmental, economic, social, and behavioural conditions and cultural patterns of living etc.
2. PRIMARY PREVENTION – to inhibit the onset of disease, which removes the possibility that the disease will ever occur.
Primary prevention is subdivided into two:
i. Health promotion – enabling people to increase control over the determinants of health and thereby improve their health. This is the concept of “positive health.” The prototype of Health Promotion is ‘Health Education’ aimed at encouraging ‘Lifestyle Modification’.
ii. Specific protection – activities which protect people from specific threats to health, such as certain diseases or accidents. The prototype of specific protection is vaccination.
3. SECONDARY PREVENTION attempts to arrest the disease process in its early stage (that is, while it is asymptomatic and before it causes any irreversible changes or damage)
Secondary prevention is subdivided into
i. Early diagnosis, for example through screening which could either be mass screening or screening of high-risk individuals
ii. Early treatment
4. TERTIARY PREVENTION is subdivided into two (Disability limitation and Rehabilitation)
i. Disability limitation which is further classified into two:
a. Prevention of complications
b. Prevention or postponement of death
ii. Rehabilitation which is of four different types:
a. Medical rehabilitation – restoration of function
b. Vocational rehabilitation – restoration of the capacity to work
c. Social rehabilitation – restoration of social relationships
d. Psychological rehabilitation – restoration of personal dignity and confidence.
5. QUATERNARY PREVENTION is the set of health activities to mitigate or avoid the consequences of unnecessary, excessive or otherwise ill-advised intervention of the health system. It includes the prevention of Overdiagnosis, Overtreatment, Cascade effect, Disease mongering and Iatrogenesis.
There are two principal means of Quaternary prevention, viz:
i. Narrative based Medicine – to listen better to our patients and to adapt the medically possible to the individual needs and wants.
ii. Evidence-based medicine – debriefing, quality assurance, and improvement processes which complete the cycle of prevention by collecting information about the processes, multi-disciplinary analysis of the data, deriving conclusions, and distributing them to all the involved bodies.