Notes:

The figures are not a count of people as the same person may have had more than one episode of care within the same time period. Information relating to the patient's diagnosis is based only on the final episode of the spell.

Length of stay is defined as the difference in days between the admission date and the episode end date (duration of episode) or discharge date (duration of spell), where both dates are given. Length of stay is based on hospital stays and only applies to ordinary admissions not day cases (unless otherwise stated). Information relating to length of stay, including discharge method/destination, diagnoses and any operative procedures, is based only on the final episode of the spell.

A discharge episode is the last episode during a hospital stay (a spell), where the patient is discharged from the hospital or transferred to another hospital. Discharges do not represent the number of patients, as a person may have more than one discharge from hospital within the period.

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 data set and provides the main reason why the patient was admitted to hospital.