Characteristics of centres invited to participate in process mapping
| Vascular surgery unit | Catchment population | Involved in PAD-QIP? | North/south |
| Unit A | 2.2 million | Yes | North |
| Unit B | 0.7 million | Yes | North |
| Unit C | 0.7 million | No | South |
| Unit D | 1.2 million | No | North |
| Unit E | 1.0 million | No | South |
| Unit F | 1.4 million | No | North |
| Unit G | 0.4 million | No | North |
| Unit H | 0.4 million | No | South |
| Unit I | 1.2 million | No | North |
| Unit J | 1.3 million | Yes | South |
| Unit K | 1.8 million | No | South |
| Unit L | 1.6 million | Yes | North |
| Unit M | 1.7 million | Yes | South |
| Unit N | 2.8 million | No | South |
PAD-QIP, Peripheral Arterial Disease Quality Improvement Programme.