Syndromology: an updated conceptual overview. II. Syndrome classifications

There are many ways to classify syndromes. In Part II, some general types of classification are considered including etiologic classification, embryonic/histologic classification, and syndrome prototypes. Polythetic classifications, in which syndromes are grouped because of their overall similarity, are then contrasted with the more commonly used monothetic classifications, in which syndromes are grouped together because they share a single feature in common. The general survey concludes with a discussion of mixed classifications. Finally, two contrasting craniofacial classifications--the Tessier classification and the morphogenetic classification--are considered.