Age (at end and start of hospital episode)

• Age (at end and start of hospital episode)

• Sex

• Ethnicity

• Duration of episode

• Type of episode (related to treatment given)

• Diagnosis category (International Classification of Diseases and related health problems [ICD-10] classification) – contains information on every known illness/disease/injury

• Separate classifications for maternity and mental health episodes

• Type of operation (if applicable)