Free breakfasts in schools: design and conduct of a cluster randomised controlled trial of the Primary School Free Breakfast Initiative in Wales [ISRCTN18336527]

Table 1 Response rates and reasons for non-participation amongst students within control and intervention schools, at baseline, 4-month and 12-month follow up

	Intervention			Control
	DC1	DC2	DC3	DC1	DC2	DC3
Sampled	2484	2533	2569	2442	2437	2493
Parent refusal	12	0	2	6	0	0
Left school	9	34	60	11	20	41
Eligible	2463	2499	2507	2425	2417	2452
Data collected	2205	2201	2272	2145	2157	2200
Data missing/invalid	18	13	5	14	8	31
Excluded due to special educational needs	37	19	11	23	16	7
Child refusal	3	0	2	3	6	7
Absent	200	266	217	228	230	205
Class unavailable on day of testing	0	0	0	12	0	0

ISSN: 1471-2458