SNOMED CT

1. Hierarchies

1.1. 19 Total Top level

1.2. Each has Sub-Hierarchies

1.3. A concept can be present in more than one category

2. Concepts

2.1. Concept ID

2.1.1. Item id

2.1.1.1. up to 15

2.1.2. Partition id

2.1.2.1. 2

2.1.3. Check Digit

2.1.3.1. 1

2.2. Descriptions

2.2.1. 2 or more

2.2.1.1. FSN

2.2.1.1.1. Only one per concept

2.2.1.1.2. has a suffix or semantic tag

2.2.1.2. PT

2.2.1.2.1. usually one per concept

2.2.1.2.2. Used in UI

2.2.1.3. SYN

2.2.1.3.1. 0..n

2.2.1.3.2. Can be found in different concepts

2.2.2. Description ID

2.2.2.1. item Id

2.2.2.1.1. 8

2.2.2.2. namespace id

2.2.2.2.1. 7

2.2.2.3. Partition id

2.2.2.3.1. 2

2.2.2.4. Check digit

2.2.2.4.1. 1

2.3. Relationships

2.3.1. IS A

2.3.1.1. Parent/Child

2.3.1.2. Many to Many

2.3.1.3. each concept has at least one parent, except root

2.3.2. Attribute Relationships

2.3.2.1. Between hierarchies

2.3.2.2. eg. Finding Site

2.3.3. Qualifier