Files Available
- Metadata files are used by the NHS to validate data. The files facilitate data consistency and quality. The files are:
- Diagnosis (International Classification of Diseases (ICD))
- Frozen Postcode Directory
- Country Pseudo Postcodes
The International Classification of Diseases (ICD)) file is issued by NHS Connecting for Health, from whom a specification is available. It is intended to reissue this file in line with the International Classification of Diseases (ICD)) updates.
The OPCS-4 metadata file and specification is issued by the NHS Classifications Service to support implementation of new releases; see Contact Details.
The full and reduced versions of the NHS Postcode Directory are issued every quarter by the Organisation Data Service. Named recipients both inside the NHS and other recipients licensed to use this data in support of the NHS are able to access it through the online distribution service, Technology Reference Data Update Distribution Service (TRUD) and through the Organisation Data Service pages on NHSnet; see Contact Details.
A full description of the NHS Postcode Directory and the Organisation Data Service reduced postcode data files, can be found by browsing the Office for National Statistics Data section of the Organisation Data Service pages on NHSnet at:
The same descriptions can also be accessed via the Technology Reference Data Update Distribution Service (TRUD).
Any area within the NHS taking advantage of the supply of metadata by the Office for National Statistics will be expected to abide by any rules and conditions imposed by the Office for National Statistics Section supplying the metadata.
Format of Metadata Files
The following pages give the record layouts and data content for the Operation and Country Pseudo Postcode metadata files.
Country Pseudo Postcode File DataContent
This file contains about 130 records. The usual country of residence for short term Overseas Visitors is derived from the country pseudo postcode. The codes are available in electronic format on the NHS Postcode Directory ("Gridlink version").
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