Table 4.

Multivariable logistic regression model for the association between maternal ethnicity and iron deficiency and iron deficiency anaemia

Variable	Iron deficiency (ID)			Iron deficiency Anaemia (IDA)
	ß (95% CI)	OR (95% CI)	P value	ß (95% CI)	OR (95% CI)	P value
Maternal ethnicity
European		Referent			Referent
East Asian	−1.013 (−1.947 to −0.079)	0.36 (0.14 to 0.92)	0.03*	−1.025 (−3.039 to 0.989)	0.36 (0.05 to 2.69)	0.32
Southeast Asian	−0.355 (−1.337 to 0.627)	0.70 (0.26 to 1.87)	0.48	−0.658 (−2.708 to 1.392)	0.52 (0.07 to 4.02)	0.53
South Asian	0.518 (0.043 to 0.993)	1.68 (1.04 to 2.70)	0.03*	0.190 (−0.661 to 1.040)	1.21 (0.52 to 2.83)	0.66
West Asian/North African	0.876 (0.031 to 1.722)	2.40 (1.03 to 5.60)	0.04*	−0.707 (−2.817 to 1.404)	0.49 (0.06 to 4.07)	0.51
African and Caribbean	−0.515 (−1.397 to 0.367)	0.60 (0.25 to 1.44)	0.25	0.246 (−0.875 to 1.367)	1.28 (0.42 to 3.92)	0.67
Latin American	−0.244 (−1.100 to 0.612)	0.78 (0.33 to 1.85)	0.57	−0.230 (−1.759 to 1.300)	0.79 (0.17 to 3.67)	0.77
Indigenous	0.502 (−1.885 to 2.890)	1.65 (0.15 to 17.99)	0.68	1.745 (−0.832 to 4.322)	5.73 (0.44 to 75.37)	0.18
Mixed	0.455 (−0.107 to 1.018)	1.58 (0.90 to 2.77)	0.11	0.757 (−0.084 to 1.597)	2.13 (0.92 to 4.94)	0.08
Child sex
Male		Referent			Referent
Female	−0.129 (−0.427 to 0.169)	0.88 (0.65 to 1.18)	0.40	−0.216 (−0.737 to 0.305)	0.81 (0.48 to 1.36)	0.42
Child's age, months†
12–15	0.215 (0.005 to 0.425)	1.24 (1.01 to 1.53)	0.04*	0.274 (−0.057 to 0.605)	1.31 (0.94 to 1.83)	0.10
15–18	−0.078 (−0.257 to 0.101)	0.92 (0.77 to 1.11)	0.39	−0.292 (−0.588 to 0.004)	0.75 (0.56 to 1.00)	0.05
18–24	−0.009 (−0.083 to 0.065)	0.99 (0.92 to 1.07)	0.81	−0.003 (−0.135 to 0.129)	1.00 (0.87 to 1.14)	0.97
24–38	−0.111 (−0.158 to -0.066)	0.89 (0.85 to 0.94)	<0.0001*	−0.206 (−0.344 to −0.068)	0.81 (0.71 to 0.93)	0.003*
CRP level, mg/L	−0.387 (−0.597 to −0.177)	0.68 (0.55 to 0.84)	0.0003*	−0.114 (−0.353 to 0.125)	0.89 (0.70 to 1.13)	0.35
zBMI	0.126 (−0.020 to 0.271)	1.13 (0.98 to 1.31)	0.09	0.086 (−0.172 to 0.343)	1.09 (0.84 to 1.41)	0.51
Birth weight, kg
≥2.5		Referent			Referent
<2.5	0.266 (−0.222 to 0.754)	1.31 (0.80 to 2.13)	0.28	−0.361 (−1.365 to 0.643)	0.70 (0.26 to 1.90)	0.48
Maternal education
Post-Secondary		Referent			Referent
No post-secondary	0.174 (−0.402 to 0.751)	1.19 (0.67 to 2.12)	0.55	1.204 (0.415 to 1.992)	3.33 (1.51 to 7.33)	0.003*
Family income (CAN $)
$80 000+		Referent			Referent
$30 000–$79 999	−0.305 (−0.763 to 0.152)	0.74 (0.47 to 1.16)	0.19	−0.425 (−1.249 to 0.399)	0.65 (0.29 to 1.49)	0.31
Less than $30 000	0.647 (0.032 to 1.261)	1.91 (1.03 to 3.53)	0.04*	0.552 (−0.368 to 1.471)	1.74 (0.69 to 4.36)	0.24
Breastfeeding Duration, months‡	0.051 (0.025 to 0.076)	1.05 (1.03 to 1.08)	0.0001*	0.057 (0.008 to 0.105)	1.06 (1.01 to 1.11)	0.02†
Bottle Use >15 months
No		Referent			Referent
Yes	0.099 (−0.280 to 0.478)	1.10 (0.76 to 1.61)	0.61	0.437 (−0.251 to 1.125)	1.55 (0.78 to 3.08)	0.21
Current infant formula use
No		Referent			Referent
Yes	−2.256 (−3.303 to −1.209)	0.10 (0.04 to 0.30)	<0.0001†	−1.949 (−3.418 to −0.480)	0.14 (0.03 to 0.62)	0.009*
Cow's milk consumption
Two cups (500 mL) or less		Referent			Referent
More than two cups (500 mL)	0.474 (0.153 to 0.795)	1.61 (1.17 to 2.21)	0.004*	−0.084 (−0.676 to 0.508)	0.92 (0.51 to 1.66)	0.78

All models adjusted for age, sex, zBMI, birth weight, maternal education, family income, CRP, breastfeeding duration (continuous variable), cow’s milk >2 cups, bottle use >15 months, infant formula use (Y/N).

*Statistically significant findings at p<0.05.

†Restricted cubic spline (RCS) analysis was used for child age.

‡Breastfeeding duration was included in model as a continuous variable.

CRP, C reactive protein; zBMI, body mass index z score.