HES Data Dictionary
HES Data Dictionary Help Reference
The Hospital Episode Statistics (HES) database is made up of many data items relating to admitted patient care delivered by NHS hospitals in England. Many of these items form part of the national Commissioning Data Set (CDS), and are generated by the patient administration systems within each hospital.
In addition to the CDS items, HES provides information that is derived from these. For example, the age of the patient is derived from their date of birth. These derivations assist in the production of aggregate summaries (tabulations), and also help ensure patient confidentiality.
HES contains data from 1 April 1989. Over the years, there have been several changes in the specification and meaning of various data items. From April 2003, this data was available in a normalised form that makes interpretation easier. This has been achieved by modifying the values of certain items for previous years so that, where possible, they conform to contemporary standards. This issue of the Data Dictionary reflects the situation after normalisation.
To locate specific items within the dictionary, use the listings accessed by clicking either Fields, Item Names or Categories. Each list contains all of the items, but arranged in a different order and style. If you are unfamiliar with CDS data item names and other conventions, it is best to use the Categories list.