The pattern of disease encountered in a hospital is quite different from that in a community.
In the community/society a far larger proportion of disease (e.g., diabetes, hypertension) is hidden from view of the general public or physician.
In this context the analogy of an iceberg is widely used to describe the disease pattern in the community.
The concept of the "iceberg phenomenon of disease"gives an idea of the progress of a disease from its sub-clinical stages to overt or apparent disease state.
The submerged portion of the iceberg represents the hidden mass of the disease (e.g., subclinical cases, carriers, undiagnosed cases).
The floating tip represents what the physician sees in his practice/chamber/hospital etc.
The remaining Large Hidden part of the iceberg is what constitutes the mass of unrecognized disease in the community.