Table 1. Cohort of school children by city, Yucatan, 2015 to 2016.

2015ʹs Cohort (Y1)		Merida		Progreso		Ticul		Total
		N	(%)	N	(%)	N	(%)	N	(%)
Recruitment	Index children	463	51	153	53	151	47	767	50
	Siblings	448	49	136	48	170	53	754	50
	Total	911	100	289	100	321	100	1521	100
Lost to follow up	Index children	149	32	21	14	19	13	189	25
	Siblings	155	35	23	17	44	26	222	29
	Subtotal	304	33	44	15	63	20	411	27
Follow up	Index children	314	68	132	86	132	87	578	75
	Siblings*	347	65	147	83	134	74	628	71
Baseline cohort (Y1)	Total	661	100	279	100	266	100	1206	100
New participants (2016)	Index children	171	48	66	47	69	48	306	48
	Siblings	185	52	73	53	74	52	332	52
	Subtotal	356	100	139	100	143	100	638	100
Cohort 2016 (Y2)	Index children	485	48	198	47	201	49	884	48
	Siblings	532	52	220	53	208	51	960	52
Total cohort		1017	100	418	100	409	100	1844	100

*Total includes siblings not participating in Y1 but decided to participate in Y2.