NHS Information Authority

Data Standards Programme

The Organisation Codes Service (OCS) have changed the postcode files used to 'Gridlink'. This is a high quality postcode-based dataset created by a consortium comprising the Office for National Statistics, Ordnance Survey, Royal Mail, Ordnance Survey of Northern Ireland and the General Register Office for Scotland.

This DSCN updates the supporting information held for the NHS Postcode Directory to reflect the new file source and contact details. The relevant organisational changes identified in 'Shifting the Balance of Power' have also been included.

METADATA FILES

Metadata Files

METADATA FILES

Files Available

1. Metadata files are used by the NHS to validate data. The files facilitate data consistency and quality. The files are:
   
   
   • Diagnosis (ICD-10)
   
   
   • Operation (OPCS-4) Fourth Revision Consolidated Version
   
   
   • NHS Postcode Directory
   
   
   • Frozen Postcode Directory
   
   
   • Country Pseudo Postcodes.

2. The ICD-10 file is issued by the NHS Information Authority, from whom a specification is available. It is intended to reissue this file annually, if required.

2. The ICD-10 file is issued by the NHS Information Authority, from whom a specification is available. It is intended to reissue this file in line with the ICD-10 updates.

3. The Operation metadata file is also issued by the NHS Information Authority on request. No update of this file is currently envisaged.

4. The NHS Postcode Directory is maintained, on behalf of the Department of Health, by the Office for National Statistics (ONS). The full NHS Postcode Directory on CD-ROM is provided free, every quarter, by the Organisation Codes Service. A reduced version of the full NHS Postcode Directory, containing Postcode, Health Authority Code and Primary Care Group/Trust Code, is provided every quarter on CD-ROM and via NHSnet as part of the standard Organisation Codes Service data issue; see Contact Details.

4. The NHS Postcode Directory (''Gridlink" version) is maintained, on behalf of the Department of Health, by the Office for National Statistics (ONS). The full NHS Postcode Directory on CD-ROM and via the NHSnet is provided free to the NHS, every quarter, by the Organisation Codes Service. A reduced version of the full NHS Postcode Directory, containing Postcode, Strategic Health Authority Code and Primary Care Group/Trust/Care Trust Code, is provided every quarter on CD-ROM and via NHSnet as part of the standard Organisation Codes Service data issue; see Contact Details.

5. A new version of the full Postcode Directory (the Gridlink version) is now issued in parallel with the current version, commencing with the November 2000 release. The Gridlink version provides more detailed and more accurate postcode grid referencing.

5. A version of the Central Postcode Directory (CPD), the 91-based Frozen Postcode Directory, is produced by the ONS to provide a stable base to facilitate time source analysis. Full details are set out in the CPD User Guide available from ONS; see Contact Details.

6. Any area within the NHS taking advantage of the supply of metadata by ONS will be expected to abide by any rules and conditions imposed by the ONS Section supplying the metadata.

Media

7. NHS Information Authority Metadata files are normally supplied on disk. Potential users should contact the NHS Information Authority Coding and Classification Help Desk on 0121 333 0420 (direct line).

Format of Metadata Files

8. The following pages give the record layouts and data content for the Operation and Country Pseudo Postcode metadata files.

Operation File Data Content

9. This file consists of about 7,000 records, one record for each operation (OPCS-4) Fourth Revision Consolidated Version used in the HES processing system. The records are in operation code order. Each record also contains editing parameters used in validation.

OPERATION FILE RECORD LAYOUT

Start Position	Size	Occurs	Field Description
1	11		selection indicators
12	1		operation prefix
13	4		operation code
17	8		filler
25	55		operation name (3 digit)
80	5		filler
85	60		operation name (4 digit)
145	43		filler
188	1		sex (absolute)
189	3		filler
192	1		sex (scrutiny)
193	1		filler
194	2		status of operation
196	23		filler
219	1	10	method of delivery
229	24		filler

OPERATION FILE FIELD CONTENTS

Field	Content
Operation Prefix	space
Operation Code	4 chars, 1 alphanumeric + 3 numeric
Sex (absolute)	space = accept any sex code 1 = males not accepted 2 = females not accepted
	1 = males not accepted
	2 = females not accepted
Sex (scrutiny)	space = accept any sex code
	1 = males not accepted
	2 = females not accepted
NB The following relate to primary operation only
Status of Operation	if status not = 01, reject for scrutiny
Method of Delivery	10 one character codes representing the DELMETH code values 0 - 9. Check character position corresponding to DELMETH code value space = no check required 1 = reject for scrutiny

Country Pseudo Postcode File Data Content

10. This file contains about 130 records. The usual country of residence for short term overseas visitors is derived from the country pseudo postcode, these can be found by browsing the following Department of Health website: http://www.nhsia.nhs.uk/ocs/onsdata.htm. This website is only available on the NHSnet. The codes are also available in electronic format on the NHS Postcode Directory.

11. The expanded area code field contains the country of birth code in characters 1-4 (a repeat of the characters 3-6 in the pseudo postcode). The remainder of the expanded area code is blank except for codes 993C (UK nos) and 993V (no fixed abode) where characters 5-7 are 9space9.

COUNTRY PSEUDO FILE RECORD LAYOUT

Start Pos	Size	Data Type	Field Description
1	11	X	selection indicators
12	6	X	6 digit postcode (POSTSIX)
18	1	A	7th digit
19	6	X	filler
25	50	X	name of country
75	5	X	filler
80	19	X	area details
99	154	X	filler

NHS POSTCODE DIRECTORY

NHS Postcode Directory

NHS POSTCODE DIRECTORY

1. The NHS Postcode Directory is maintained, on behalf of the Department of Health, by the Office for National Statistics (ONS). It contains a record for every postcode in the UK, Channel Islands and the Isle of Man, and associates each postcode with a variety of geographic information, including grid references, Primary Care Groups, Primary Care Trusts and Health Authority codes. The file also includes pseudo postcodes covering defaults and overseas countries.

1. The NHS Postcode Directory is maintained, on behalf of the Department of Health, by the Office for National Statistics (ONS). It contains a record for every postcode in the UK, Channel Islands and the Isle of Man, and associates each postcode with a variety of geographic information, including grid references, Primary Care Groups, Primary Care Trusts and Strategic Health Authority codes. The file also includes pseudo postcodes covering defaults and overseas countries.

2. The full and reduced versions of the NHS Postcode Directory are issued every quarter by the Organisation Codes Service (OCS). A CD-ROM is sent to named recipients both inside the NHS and to other recipients licensed to use this data in support of the NHS. Both versions of the NHS Postcode Directory are also available via the NHSnet.

3. A full description of the NHS Postcode Directory and the OCS reduced postcode data files, can be found by browsing the following Department of Health website: nww.nhsia.nhs.uk/ocs/onsdata.htm. This website is only available on the NHSnet. Please see Contact Details.

3. A full description of the NHS Postcode Directory and the OCS reduced postcode data files, can be found by browsing the following website: nww.nhsia.nhs.uk/ocs/onsdata.htm. This website is only available on the NHSnet. Please see Contact Details.

4. The ONS will supply, on request and at a cost, copies of the NHS Postcode Directory, on different media, in different formats and for selected extracts. Contact the ONS for details and charges; See Contact Details.

Postcodes

5. All postcodes made available via OCS postcode files have been standardised to the eight character postcode format as used by the Royal Mail's Postal Address File (PAF). All NHS Organisations should ensure that they conform to the postcode format.

6. Postcodes are of the general format :

Character Position	1	2	3	4	5	6	7	8
Format	a	a/n	a/n	a/n	space	n	a	a
Coding Frame	Outward Code				space	Inward Code

The coding frame allows the use of digits 0 (zero) to 9 and the use of upper-case alpha characters; no special characters are allowed.

7. The coding frame allows the use of digits 0 (zero) to 9 and the use of upper-case alpha characters; no special characters are allowed.

8. The fifth character of all standard format postcodes is always a space, and separates the outward and inward parts of the postcode. The outward part of the postcode is left-justified and can contain 2, 3 or 4 characters, and is space-filled in character positions 3 and 4 where required. The inward part of the postcode is always 3 characters.

The following table gives examples of typical postcodes :

Character Position								Allocated by	Notes
1	2	3	4	5	6	7	8
1	2	3	4	5	6	7	8
W	9				3	X	X	Royal Mail
D	A	1			5	P	L	Royal Mail
M	K	4	5		1	T	E	Royal Mail
Z	Z	9	9		4	L	Z	OCS	Pseudo Postcodes, Defaults and Overseas

9. The "Scottish split postcode indicator" field was discontinued from the 1996/1 version of the NHS Postcode Directory. This value used to appear in the 8th character position of the postcode (the postcode field was then only 7 characters in length). The ‘Alternative’ version of the NHS Postcode Directory, showing postcodes containing this field, is available from the ONS.

Health Authority/Health Board Codes

Strategic Health Authority/Health Authority/Health Board Codes

10. Health Authorities in England and Wales are indicated by their standard OCS codes (Q codes). Health Boards in Scotland use a three character version of the Health Board code (range SA9 - SZ9). The four Northern Ireland Health Boards are indicated by their standard codes - ZE0, ZN0, ZS0, ZW0.

10. Strategic Health Authorities in England and Health Authorities in Wales are indicated by their standard OCS codes (Q codes). Health Boards in Scotland use a three character version of the Health Board code (range SA9 - SZ9). The four Northern Ireland Health Boards are indicated by their standard codes - ZE0, ZN0, ZS0, ZW0.

11. No Health Authorities exist for the Channel Islands and the Isle of Man so notional (or dummy) Health Authority codes are used to identify postcodes from these locations. The default Health Authority code of X98 (HA of Residence is not applicable) is used to indicate pseudo postcodes (defaults and overseas).

11. No Strategic Health Authorities exist for the Channel Islands and the Isle of Man so notional (or dummy) Strategic Health Authority codes are used to identify postcodes from these locations. The default Pseudo health authority code of X98 is used to indicate pseudo postcodes (defaults and overseas).

12. For further information on Health Authority and Health Board codes and their values, See ADMINISTRATIVE CODES.

12. For further information on Strategic Health Authority and Health Board codes and their values, See ADMINISTRATIVE CODES.

Related Products

13. The ONS produce annually two related publications : ONS Geography User Guide 9 (The Area of Residence Classification) and ONS Geography User Guide 10 (The NHS Organisation Manual). These show a breakdown of NHS Regions and Health Authorities by Local Government authorities and Electoral Wards. Copies are available from ONS. Electronic copies are also included in the full NHS Postcode Directory on CD-ROM as provided by OCS.

13. The ONS produce annually two related publications : ONS Geography User Guide 9 (The Area of Residence Classification) and ONS Geography User Guide 10 (The NHS Organisation Manual). These show a breakdown of Strategic Health Authorities by Local Government authorities and Electoral Wards. Copies are available from ONS. Electronic copies are also included in the full NHS Postcode Directory on CD-ROM as provided by OCS.

14. ONS produce a version of the Postcode Directory that is based on a stable area base to facilitate time series analysis - the 1991-based Frozen Postcode Directory. This is available from the ONS.

15. The OCS issues the full manuals on the CD-ROM each quarter. This ensures that any new customers receive the necessary information.

Changes

16. The ONS should be notified of any queries relating to the allocation of postcodes to Health Authorities. All such queries are investigated by ONS, and any agreed changes are included in the following edition of the NHS Postcode Directory. The monthly postcode corrections are also included on the NHSnet, See Contact Details.

16. The ONS should be notified of any queries relating to the allocation of postcodes to Strategic Health Authorities or Primary Care Trusts. All such queries are investigated by ONS, and any agreed changes are included in the following edition of the NHS Postcode Directory. The monthly postcode corrections are also included on the NHSnet, See Contact Details.

17. Requests and suggestions for improvements to the NHS Postcode Directory or queries relating to its use should be directed to OCS, who are taking the lead on this product on behalf of the NHS; see Contact Details.

PUBLICATION INFORMATION CONTACT DETAILS

Publication Information Contact Details

CONTACT DETAILS

Please address enquiries about this DSCN to:-
Data Standards Team
NHS Information Authority
Aqueous II
Aston Cross
Rocky Lane
Birmingham
B6 5RQ

Tel: 0121 333 0333