Each of these triangles represents a way that prevention has been illustrated as a part of the whole system that includes all forms of population and personal health care.

The primary, secondary and tertiary prevention pyramid at left is an older model, and may be confusing in its use of the term “tertiary prevention” to mean secondary and tertiary medical interventions such as surgery, chemotherapy and long-term care.

The newer pyramid at right illustrates the mid-place occupied by the clinical preventive services, which can be either population-focused or a part of personal care, and which include both primary prevention (immunization) and secondary prevention (e.g., cancer screening).

The placement of population-oriented prevention at the base is significant in

- its focus on all of the people as recipients

- its broad, long-lasting impact on health