Multiplicity
What is Multiplicity?¶
An item's Multiplicity refers to the minimum and maximum number of times it can appear within its parent in Mauro Data Mapper. For example, the number of instances a particular Data Element appears within a Data Class.
How is Multiplicity used?¶
Every Data Class and Data Element is assigned a Multiplicity. Typically, the Multiplicity is written in the form ‘minmax’, where min and max are integers representing the minimum and maximum number of times an item will appear within its parent. The symbol * represents an unbounded maximum.
- Using this notation:
- Mandatory data has a minimum Multiplicity of 1 and a maximum Multiplicity of a specific integer or if there is no upper bound, then '*' (which is represented by '-1' internally).
- Optional data has a minimum Multiplicity of 0 and a maximum Multiplicity of 1 or if there is no upper bound, *.
For example, each person in a Data Model only has one date of birth and if you want to record this, then the corresponding Multiplicity will be 1..1. However, each person may have many prescription records, which may or may not be relevant. In this case, the Multiplicity would be 0..*.
Furthermore, each person will only have one date of death, which again you may or may not want to record, so the Multiplicity for this would be 0..1.
How do you edit an item's Multiplicity?¶
The Multiplicity can be found in the details panel of Data Classes and Data Elements. It is a mandatory field when adding or importing a Data Class or Data Elements, as explained in the 'Document a Health Datatset user guide' and 'Import a Data Model from Excel user guide'.
You can edit the Multiplicity of an item by selecting it in the Model Tree and clicking the ‘Edit’ pencil icon at the bottom right of the details panel. You will then be able to amend the min and max values of that item's Multiplicity.
