Notes:

Finished Consultant Episode (FCE)

1. A FCE is defined as a continuous period of admitted patient care under one consultant within one health care provider. FCEs are counted against the year in which the FCE finishes. Please note that the figures do not represent the number of patients, as a person may have more than one episode of care within the year.

*Primary diagnosis

2. The primary diagnosis is the first of up to 20 (14 from 2002-03 to 2006-07 and seven prior to 2002-03) diagnosis fields in the Hospital Episode Statistics (HES) data set and provides the main reason why the patient was in hospital.

E66—Obesity.

Number of episodes in which the patient had a (named) primary diagnosis

3. These figures represent the number of episodes where the diagnosis was recorded in the primary diagnosis field in a HES record.

**Main procedure

4. The main procedure is the first recorded procedure or intervention in the HES data set and is usually the most resource intensive procedure or intervention performed during the episode. It is appropriate to use main procedure when looking at admission details, e.g. time waited, but a more complete count of episodes with a particular procedure is obtained by looking at the main and the secondary procedure.

Data Quality

5. HES are compiled from data sent by more than 300 NHS trusts and primary care trusts (PCTs) in England. Data is also received from a number of independent sector organisations for activity commissioned by the English NHS. The NHS Information Centre for health and social care liaises closely with these organisations to encourage submission of complete and valid data and seeks to minimise inaccuracies and the effect of missing and invalid data via HES processes. While this brings about improvement over time, some shortcomings remain.

Assessing growth through time

6. HES figures are available from 1989-90 onwards. During the years that these records have been collected by the NHS there have been ongoing improvements in quality and coverage. These improvements in information submitted by the NHS have been particularly marked in the earlier years and need to be borne in mind when analysing time series. Some of the increase in figures for later years (particularly 2006-07 onwards) may be due to the improvement in the coverage of independent sector activity.

Changes in NHS practice also need to be borne in mind when analysing time series. For example, a number of procedures may now be undertaken in out-patient settings and may no longer be accounted for in the HES data. This may account for any reductions in activity over time.

Ungrossed Data

7. Figures have not been adjusted for shortfalls in the data, i.e. the data are ungrossed.

Primary Care Trust (PCT)/Strategic Health Authority (SHA) data quality

8. PCT and SHA data was added to historic data years in the HES database using 2002-03 boundaries, as a one-off exercise in 2004. The quality of the data on PCT of treatment and SHA of treatment is poor in 1996-97, 1997-98 and 1998-99, with over a third of all finished episodes having missing values in these years. Data quality of PCT of GP practice and SHA of GP practice in 1997-98 and 1998-99 is also poor, with a high proportion missing values where practices changed or ceased to exist. There is less change in completeness of the residence-based fields over time, where the majority of unknown values are due to missing postcodes on birth episodes. Users of time series analysis including these years need to be aware of these issues in their interpretation of the data.

Source:

Hospital Episode Statistics (HES), The NHS Information Centre for health and social care