Cost-effective recruitment methods for a large randomised trial in people with diabetes: A Study of Cardiovascular Events iN Diabetes (ASCEND)

Table 1 Recruitment by route of identification

	Central registers	General practitioner (GP) registers	Others^a	Total (% of those invited)
Invited	300,188	120,875^b	2340	423,403
Returned valid screening form	100,563	19,478	1213	121,254 (29 %)
Entered run-in	16,091	9739	632	26,462 (6 %)
Sent randomisation form	13,481	8541	557	22,579 (5 %)
Randomised (% of those invited)	9013 (3 %)	6037 (5 %)	430 (18 %)	15,480 (4 %)

^aMRC/BHF Heart Protection Study/self-referral/Friends & Family referral/consultant clinic invitations
^bBased on number of screening forms sent by coordinating centre to GP practices to be mailed to participants

ISSN: 1745-6215