SNOB - A SNOMED Browser

Manual

Navigational Subsets

SNOB treats navigational subsets differently from other subsets. The navigational subsets are listed at the the bottom of the subsets window. When you select one of these subsets, SNOB uses the relationships defined in that subset for the hierarchy in the browser.

SNOB reports two kinds of problems for navigational subsets. The first problem is when a navigational subset duplicates information:

duplicated row 103379005.103362004 in navigational subset 168037

The second problem is when a concept in the navigational subset is an orphan, i.e. it doesn't have a parent that links it to the top concept.

orphaned concept 395441002 in navigational subset 168037
orphaned concept 246188002 in navigational subset 104038

SNOB creates a relationship for orphaned concepts directly to the top concept SNOMED CT Concept.