If you have nothing better to do on a wet windy grey afternoon and you are desperately bored, then here is something to occupy your mind and time. The Department of Health regularly publishes reports that record inpatient and outpatient hospital activity under the heading “Hospital Episode Statistics” (HES).1 HES began in 1987 following a report on the collection and use of hospital activity information. Before 1987 only 10% of admitted patient records were collected nationally. HES aims to collect a detailed record for each “episode” of admitted patient care delivered in England by NHS hospitals or delivered in the independent sector but commissioned by the NHS.

Data are available for every financial year from 1989–90 onwards. During this period the mechanisms for collecting the data have changed, often in response to changes in NHS organisation—for example, regional health authorities once initially collated HES sub-nationally. In 1996 these bodies were abolished and the NHS-Wide Clearing Service (NWCS) was set up. The work of the NWCS was then taken over by …