A hierarchical organization of terms or ideas that allows aggregation into categories. 

Notes

• A statistical classification
  • Allows categories to be counted and compared, without double counting.
  • Is a

    Gloss
    t monohierarchical classification

    , which mean that each node in the

    Gloss
    t hierarchy

    is included in only one node in the level above. Although this avoids double counting, it means that arbitrary decisions are made when a node is naturally related to more than one parent. 

Example

• In a statistical classification such as

  Gloss
  t ICD-10

  , bacterial pneumonia is related to lung disorder or infectious disorder, but not to both.

Hierarchy Illustration - Statistical Monohierarchical Classification

• In contrast, a 

  Gloss
  t polyhierarchical classification

   such as SNOMED CT, enables bacterial pneumonia to be a subtype of both lung disorder and infectious disorder. This enables more inclusive analytics and avoids overlooking conditions that are in a different category from the one being analyzed.

Hierarchy Illustration - Subtype Polyhierarchy

Related Links

• Gloss
  t Monohierarchical classification

• Gloss
  t Polyhierarchical classification

• Gloss
  t Subtype classification

• Gloss
  t Directed acyclic graph