Data Set Constraints applied to the Mental Health Services Data Set.
Key to Data Set Constraint Column Headings:
| Column Name | Column Meaning | Column Options | |
| Format/Length | Indicates any differences between the Format/Length of the item in the NHS Data Model and Dictionary and the data set specification | None = The Format/Length is the same as the NHS Data Model and Dictionary | Any other entry = The Format/Length is different in the data set specification to the NHS Data Model and Dictionary |
| Range | Indicates whether a range value constraint has been applied in the data set specification | None = There is no range value constraint applied in the data set specification | Any other entry = Shows the range value constraint applied in the data set specification |
| Pattern Match | Indicates whether a data pattern, to which the data must conform, has been applied in the data set specification | None = There is no data pattern, to which the data must conform, applied in the data set specification | Any other entry = Shows the data pattern, to which the data must conform, applied in the data set specification |
Data Set Constraints:
| Data Element | Format/Length | Range | Pattern Match | Reason / Comment |
| ETHNIC CATEGORY | max an2 | None | None | Existing Format/Length means fixed length which is incorrect. Unable to change this as it is used in other data sets. Data Set allows max an2 |
| INDIRECT ACTIVITY PROCEDURE (SNOMED CT EXPRESSION) | min an6 max an56 | None | None | The SNOMED CT EXPRESSION base data element is not defined with a maximum length. This data item constraint has been constrained to the recommended length for the MHSDS. |
| PATIENT SELF-DIRECTED DIGITAL INTERVENTION PROCEDURE (SNOMED CT EXPRESSION) | min an6 max an56 | None | None | The SNOMED CT EXPRESSION base data element is not defined with a maximum length. This data item constraint has been constrained to the recommended length for the MHSDS. |
| PROCEDURE (SNOMED CT EXPRESSION) | min an6 max an56 | None | None | The SNOMED CT EXPRESSION base data element is not defined with a maximum length. This data item constraint has been constrained to the recommended length for the MHSDS. |
| REFERRAL PROCEDURE (SNOMED CT EXPRESSION) | min an6 max an56 | None | None | The SNOMED CT EXPRESSION base data element is not defined with a maximum length. This data item constraint has been constrained to the recommended length for the MHSDS. |
| UNIT OF MEASUREMENT (UCUM) | max an20 | None | None | The format/length of the UNIT OF MEASUREMENT (UCUM) is unconstrained in the NHS Data Model and Dictionary. The MHSDS constrains the format/length to max an20 |