Foundation and linearizations: multiple parenting and specialty lists

One entity, two homes

How does the Foundation let a condition belong in more than one place?

Correctly in two places

An entity can be correctly classified in two places, by site or by aetiology. Oesophageal cancer can sit under neoplasms or under digestive conditions. Cerebral ischaemia under the vascular system or the nervous system. The choice depends on international agreement and legacy.

• 0 · 0 · exact
• 0 · 1 · exact
• 1 · 2 · exact
• 1 · 3 · exact

One parent in the list

In a tabular list the category has exactly one parent. The information about its other parents stays available from the Foundation, so a category can appear in black in its place, and in grey elsewhere, for browsing.

• The category · One parent · In a tabular list each category has exactly one parent.
• The rest · Kept · Information about the other parents remains available from the Foundation.
• Display · Black, grey · A category can show in black in its place and in grey in other places for browsing.

A list as a second parent

Where data need to be tabulated another way, WHO creates a special linearisation list as a second parent. The coding scheme of the entries stays the one used for the full classification. There are specialty lists, for example for primary care, dermatology and mental health.

• Alternative tabulation · Second parent · Where data must be tabulated another way, create a special linearisation as a second parent.
• The code · Unchanged · The coding scheme of the entries remains the one used for the full international classification.
• Examples · Specialty · For example primary care, dermatology and mental health.

Lists for particular uses

Special tabulation lists continue, with two additions: the Startup Mortality List and a list for verbal autopsy. More can be derived from multiple parenting, such as all WHO notifiable diseases.

• Existing · Continue · Special tabulation lists from ICD-10 continue, plus the Startup Mortality List and a verbal autopsy list.
• Derived · From parenting · Further lists can be derived from multiple parenting, such as all WHO notifiable diseases.

Check yourself

Pause and think. Why can the Foundation place oesophageal cancer under both neoplasms and digestive conditions? The answer: An entity can be correctly classified in two places, by aetiology and by site. WHO describes multiple parenting: oesophageal cancer can sit under neoplasms or under digestive conditions. Which place is used depends on international agreement and legacy.

• One of the two placements is an error
• An entity can be correctly classified in two places, by aetiology and by site
• The entity has two different codes
• Digestive conditions is only a display grouping

Keep these in mind

The foundation allows several parents. A list category has exactly one. And linearizations are lists derived for a purpose.

• The Foundation allows several parents
• A list category has exactly one
• Linearizations are lists derived for a purpose