History description 2014-03-26: Lock all vaue sets untouched since 2014-03-26 to trackingId 2014T1_2014_03_26

A group of entries within a composition, topic or category that have a logical association with one another.

The representation of a single observation or action might itself be multi-part. The data might need to be represented as a nested set of values, as a table, list, or as a time series. The Cluster class permits such aggregation within an entry for such compound data.

Examples include "Haematology investigations" which might include two or more distinct batteries.

A cluster may contain batteries and/or individual entries