A cluster is the term for a group of NHS organisations with similar characteristics, which allows comparisons to be made between trusts in similar circumstances. Details are found below.
| Description | Number of trusts in cluster |
|---|---|
| Small acute | 33 |
| Medium acute | 52 |
| Large acute | 44 |
| Acute specialist, includes acute specialist (children) | 20 |
| Acute teaching | 24 |
Note: clinical indicators are clustered differently thus splitting the acute specialist (children) from the other acute specialist.
Ambulance trusts were grouped by the Department of Health into two cluster types. These are defined as follows:
| Description | Number of trusts in cluster |
|---|---|
| Rural ambulance trusts | 23 |
| Urban ambulance trusts | 8 |
The cluster classification used for mental health trusts was provided by the Department of Health. It is recognised as being limited, only distinguishing between broad types of trust. The three groups defined are as follows:
| Description | Number of trusts in cluster |
|---|---|
| Mental health trusts | 64 |
| PCTs with mental health services | 19 |
Primary care trusts were grouped into fourteen types of clusters, as defined but the Office of National Statistics. Some cluster names have been renamed to fully reflect the type of trusts included. These are as follows:
| Description | Number of trusts in cluster |
|---|---|
| Regional centres | 19 |
| Centres with industry | 30 |
| Thriving periphery | 9 |
| Suburbs | 11 |
| Centre | 8 |
| Cosmopolitan | 9 |
| Prospering smaller towns - A | 25 |
| Prospering smaller towns - B | 28 |
| Prospering smaller towns - C | 34 |
| New and growing towns | 16 |
| Prospering southern England | 32 |
| Coastal and countryside | 30 |
| Industrial hinterlands | 25 |
| Manufacturing towns | 27 |