. 2007 Nov 30;7:345. doi: 10.1186/1471-2458-7-345

Table 3.

Ferritin concentration and prevalence of iron deficiency, by region, age group, and care regimen

Region/Age groups	Regular Regimen (RR)						IMSS-Oportunidades (IO)

	n	N	Ferritin concentration μg/L		Prevalence of iron deficiency*		n	N	Ferritin concentration μg/L		Prevalence of iron deficiency*
			Mean	95% CI	%	95% CI			Mean	95% CI	%	95% CI

North
< 6 months	84	40776	66.2	43.3, 89.0	4.3	2.6, 7.1	72	460	132.3	64.1, 200.5	6.1	2.3, 15.2
6–11 months	268	138802	30.6	25.2, 35.0	25.6	18.6, 34.2	139	1148	26.4	16.6, 36.2	36.9	30.1, 44.2
12–23 months	295	163476	16.1	12.8, 19.4	44.1	26.5, 63.3	332	3239	28.0	15.2, 40.8	43.3	32.6, 54.6
Total North	647	343054	27.9	15.3, 40.5	31.9^a	23.5, 41.6	543	4848	37.5	23.7, 51.4	38.2^a	31.7, 45.2

Center
< 6 months	147	55228	96.4	56.2, 136.6	4.6	1.5, 13.0	33	703	65.6	8.5, 122.7	13.8	8.1, 22.4
6–11 months	282	119726	30.1	25.2, 35.0	19.4	16.2, 23.0	138	3644	21.1	4.6, 37.5	49.7	30.4, 69.1
12–23 months	348	177310	18.2	13.4, 23.0	39.0	33.4, 44.8	322	9268	25.8	1.0, 58.3	48.1	37.5, 58.8
Total Center	777	352264	34.5	22.0, 47.0	26.8^a	22.7, 31.4	493	13615	26.6	1.0, 54.1	46.7^a	32.9, 61.1

South
< 6 months	25	14352	81.9	65.8, 97.9	21.0	13.5, 31.3	19	5007	50.4	33.1, 67.8	21.8	11.5, 37.5
6–11 months	239	79886	19.4	15.4, 23.4	37.3	30.4, 44.8	97	25128	59.3	24.0, 94.6	24.4	9.7, 49.1
12–23 months	401	123384	13.2	8.8, 17.5	54.4	43.8, 64.6	207	54992	35.8	16.7, 54.9	24.3	16.9, 33.6
Total South	665	217622	20.2	12.0, 27.9	46.2^a	37.4, 55.3	323	85127	43.6	18.6, 68.6	24.2^a	16.0, 34.7

Mexico City ^&
< 6 months	64	30872	87.9	70.5, 105.2	7.2	4.6, 11.2
6–11 months	152	77977	32.2	28.9, 35.6	28.8	17.7, 43.4
12–23 months	195	88543	26.4	16.2, 36.5	36.7	29.5, 44.4
Total Mexico City ^&	411	197392	38.3	25.8, 50.8	28.9^a	19.1, 41.1

NATIONAL
< 6 months	320	141228	84.3	63.2, 105.5	6.8	4.3, 10.9	124	6170	58.3	41.2, 75.4	19.7	11.4, 31.8
6–11 months	941	416391	28.6	23.9, 33.3	26.7	22.8, 30.9	374	29920	53.4	21.7, 85.1	28.0	13.2, 49.7
12–23 months	1239	552713	17.8	15.1, 20.4	43.6	37.1, 50.2	861	67500	34.0	17.9, 50.2	28.4	22.3, 35.5
TOTAL NATIONAL	2500	1110332	30.3	24.2, 36.4	32.6^b	28.8, 36.6	1359	100230	41.1	20.0, 62.1	27.8^b	20.2, 36.9

N Population size (expanded sample)

* Ferritin <10 μg/L

^& Mexico City and periurban area

^aComparing between regions within each regimen, RR = 0.015; IO = 0.007.

^bComparing between regimens, national level, p = 0.287