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Technical glossary for the Technical Output Specification

This page contains technical terms and detailed explanations to help when using the Technical Output Specification. This is a generic page that can be used across data sets, although some data sets may differ slightly from others. We have tried to reference where this is the case.  

Clinical terminology and classification validations

These validations apply to each clinical terminology data item within the data set. These items are indicated by the brackets (Coded Terminology), (Coded Clinical Entry) or (SNOMED CT).

The validations applied will be based on the corresponding Scheme In Use selected.

Scheme In Use

Format

Validation

ICD-10

min an4 max an6

Format check

OPCS-4

an4

Format check

SNOMED CT
(Procedure and Procedure Status ONLY)

min an6 max an56

Define a SNOMED CT code as:
* A string of numeric characters
* Between 6 and 18 characters in length, inclusive
* The penultimate two characters must be either "00" or "10"
* Must pass the "Verhoeff check"

When the ProcedureScheme has value "06" (ie. SNOMED CT),

Then ProcedureCode must be one of:
* A single SNOMED CT code
* A string in the form [concept identifier]:[attribute]=[value], where:
** [concept identifier] must be a SNOMED CT code
** [attribute] must be either "408730004", or "363589002"
** [value] must be a SNOMED CT code

(This may not apply to all data sets - some don’t allow strings of multiple SNOMED CT procedures (e.g. CSDS). In future this may change and we may allow other SNOMED CT codes to flow in these fields too (and extend formats, though not until the next versions of data sets).

SNOMED CT (Finding, Situation, Observation, Diagnosis)

min n6 max n18

Format check, Check Digit + Partition Identifier checks*

Read Coded Clinical Terms Version 2

an5 or an7

Format check

Read Coded Clinical Terms Version 3 (CTV3)

an5 or an7

Format check

 


Distance calculations, where used in derivations

The Northings\Eastings fields within the NHS Postcode Directory table and Pythagoras's theorem are used to calculate the distance between patient postcode and postcode of Ward/Contact/GP Practice Location.

The calculation is:
SquareRoot (((OSEAST1M(H)- OSEAST1M(L))2+( OSNRTH1M(H)- OSNRTH1M(L)) 2)

(H) designates the patient home details
(L) designates the Ward/Contact/GP Practice Location details.

How to identify the Northings/Eastings for each location

Patient Details

MPI – POSTCODE OF USUAL ADDRESS

Then identify the Northings\Eastings for this postcode by using the ONS NHS Postcode Directory file
Eastings OSEAST1M
Northings: OSNRTH1M 

GP distance from home

GENERAL MEDICAL PRACTICE CODE (PATIENT REGISTRATION).

Look up the practice's postcode in the ODS reference data file: EPRACCUR

Then identify the Northings\Eastings for the GP Practice postcode by using the ONS NHS postcode directory file
Eastings OSEAST1M
Northings: OSNRTH1M 

Contact location distance from home

SITE CODE (OF TREATMENT)

Look up the postcode for this Site Code in the ODS reference data file that holds the address for organisation sites.

Then identify the Northings\Eastings for this postcode by using the ONS NHS Postcode Directory file
Eastings OSEAST1M
Northings: OSNRTH1M

Ward location distance from home

SITE CODE (OF TREATMENT)

Look up the postcode for this SiteCode in the ODS reference data file that holds the address for organisation sites.

Then identify the Northings\Eastings for this postcode by using the ONS NHS Postcode Directory file

Eastings OSEAST1M
Northings: OSNRTH1M


Invalid values

An invalid value is a value that is invalid for a specific data item. For example, 'Q' would be an invalid value in a Y/N indicator. These records will generate a warning and an error message will be returned.


Mandation

The three phases of validation correspond to the mandation levels. So, for instance, if a data item is mandatory, it is likely to have data item level rejections for a null or invalid entry. 

While a particular table itself may not be mandatory, if a record is entered in this table then all of the table’s mandatory fields must be completed. 

Other tables only require a record to be present where applicable to the service user. For example, not all service users will have a recorded Primary Diagnosis and the Primary Diagnosis table can be left blank in these cases. If a record is entered into this table then data must be recorded against all mandatory fields. 

A mandatory data item does not mean that whole group is mandatory, it is only mandatory if the group is submitted. For example, in the Mental Health Services Data Set, EMPLOYMENT STATUS in MHS004EmpStatus is a mandatory data item. MHS004EmpStats is not a mandatory group so EMPLOYMENT STATUS only needs to be completed if MHS004EmpStatus is being submitted. 


Null values

A field with a null value is a field with no value/data. Null values must be allowed to flow provided valuation rules for the individual item have been applied. Otherwise records should not flow.  


Organisation Data Service (ODS) codes live organisation

A live organisation is an organisation that is active on the first day of the reporting period.


Organisation Data Service (ODS) codes open organisation

An open organisation is one deemed as being active during the reporting period.


Special characters

Each submitted data item and NHS Digital extract field should conform to the format specified in the Format column for the table in question. In the case of submitted data items, they must also conform to the validation rules specified in the four Validation Rules columns. 

Within these constraints, the submission portal will accept any characters present in the UTF-8 Basic Latin character set. 

Whilst the portal is not specifically designed to reject characters not appearing in this character set, their acceptance has not been tested and NHS Digital cannot guarantee that inclusion in a submission will not result in file rejection. 

The submission portal will also accept spaces where there is at least one UTF-8 Basic Latin character before and after a single space, or multiple consecutive spaces.

The portal is not designed to reject submissions that contain leading or trailing ‘white space’ in any field (e.g. spaces, tabs, carriage returns, and newline characters). Leading or trailing ‘white space’ will be removed during processing of submissions, prior to any other validation rules being applied.

In the case of NHS Digital XML extracts all submitted XML reserved characters will be replaced with their escape sequences.

XML reserved characters and their escape sequences.

< &lt;
> &gt;
& &amp;
&apos;
" &quot;

 


Validations

All data items have validations associated with them.

These validations ensure the right type of data is submitted. Validations may generate a warning that is returned with the data quality report or may cause individual data items or the whole file to be rejected. Although there are hundreds of data items, the associated error messages, warning messages and explanations can be grouped together and explained in more general terms.

Last edited: 19 January 2022 4:17 pm