Aphthous stomatitis countries. Within nations, it is more common in higher socioeconomic groups. Males and females are affected in an equal ratio, and the peak age of onset between 10 and 19 years. About 80% of people with aphthous stomatitis first developed the condition before the age of 30. There have been reports of ethnic variation. For example, in the United States, aphthous stomatitis may be three times more common in white-skinned people than black-skinned people. "Aphthous affectations" and "aphthous ulcerations" of the mouth are mentioned several times in the treatise "Of the Epidemics" (part of the Hippocratic corpus, in the 4th
Philosophy of medicine course', 'diagnosis', and 'patient'. The scope of OGMS is restricted to humans, but many terms can be applied also to other organisms. OGMS provides a formal theory of disease that is elaborated further by specific disease ontologies which extend it, including the Infectious Disease Ontology (IDO) and the Mental Disease Ontology. René Descartes made ontological space for modern medicine by separating body from mind – while mind is superior to body as it constitutes the uniqueness of the human soul (the province of theology), body is inferior to mind as it is mere matter. Medicine simply investigated(s) the body as