Table 1.

Demographic characteristics (ATP cohort for persistence).

Characteristics	Categories	MMR-RIT-1N = 189		MMR-RIT-2 N = 181		MMR-RIT-3 N = 196		M-M-R IIN = 186
Age at dose 1	Mean	12.3		12.3		12.2		12.3
(months)	SD	0.67		0.66		0.55		0.67
		n	%	n	%	n	%	n	%
Gender	Female	98	51.9	87	48.1	100	51.0	79	42.5
	Male	91	48.1	94	51.9	96	49.0	107	57.5
Race	African heritage	14	7.4	15	8.3	16	8.2	18	9.7
	American Indian or Alaskan native	0	0.0	0	0.0	0	0.0	1	0.5
	South East Asian heritage	1	0.5	1	0.6	0	0.0	0	0.0
	Pacific islander	2	1.1	0	0.0	1	0.5	2	1.1
	North African heritage	2	1.1	0	0.0	1	0.5	3	1.6
	European heritage	150	79.4	140	77.3	154	78.6	143	76.9
	Other	20	10.6	25	13.8	24	12.2	19	10.2

MMR-RIT-1: lot 1 of MMR

MMR-RIT-2: lot 2 of MMR

MMR-RIT-3: lot 3 of MMR

M-M-R II: Merck's MMR vaccine

N = total number of children

SD: Standard deviation

n/% = number / percentage of children in a given category