Site | London | Manchester | Total (London and Manchester) |
Invitation letters | 1174 | 822 | 1996 |
Practices | 17 | 22 | 39 |
Replies received (%) | 589/1174 (50.2%) | 398/822 (48.4%) | 986/1996 (49.4%) |
Letters returned to sender | 42 | 2 | 44 |
Replied but declined to take part | 174 | 239 | 413 |
Replied and agreed to take part | 415/589 (70.5%) | 159/398 (39.9%) | 574/986 (58.0%) |
Randomised | 415/415 (100%) | 152/159 (95.6%)* | 567/574 (98.9%) |
*Some Manchester practices withdrew from the trial after patients had agreed to take part but before randomisation.