Table 3.

Estimates of the effect of breastfeeding on educational achievement in sub-Saharan Africa

Study 1: Horta et al., 2013 [40]*
	Highest grade achieved at school		Completed at least 12 y of schooling
	Unadjusted mean difference (95% CI)	Adjusted mean difference (95% CI)	Unadjusted prevalence ratio (95% CI)	Adjusted prevalence ratio (95% CI)
Ever breastfeed
No	0.0	0.0	1.00	1.00
Yes	0.02 (-0.26 to 0.29)	-0.08 (-0.41 to 0.25)	0.97 (0.84 to 1.13)	0.95 (0.79 to 1.14)
Duration of any breastfeeding (in months)
≤1.00	0.0	0.0	1.00	1.00
>1-3	-0.06 (-0.32 to 0.19)	-0.23 (-0.52 to 0.05)	0.92 (0.80 to 1.05)	0.83 (0.70 to 0.98)
>3-6	-0.10 (-0.38 to 0.18)	-0.10 (-0.41 to 0.21)	0.94 (0.81 to 1.09)	0.93 (0.78 to 1.10)
>6-12	0.04 (-0.22 to 0.30)	-0.03 (-0.31 to 0.26)	0.98 (0.85 to 1.12)	0.97 (0.83 to 1.12)
>12-18	-0.02 (-0.29 to 0.25)	-0.08 (-0.37 to 0.21)	0.97 (0.84 to 1.11)	0.94 (0.80 to 1.09)
>18-24	0.16 (-0.13 to 0.45)	0.09 (-0.21 to 0.40)	1.01 (0.87 to 1.17)	1.04 (0.89 to 1.21)
>24	-0.12 (-0.37 to 0.12)	-0.02 (-0.29 to 0.24)	0.89 (0.78 to 1.02)	0.97 (0.84 to 1.12)
Study 2: Mitchell et al., 2016 [41]†
	Grade repetition
	Unadjusted odds ratio (95% CI)	Adjusted odds ratio (95% CI)	-	-
Exclusive breastfeeding for six months (Overall sample; n = 842)
0-1 mo	1.00	1.00	-	-
2-5 mo	0.77 (0.49 to 1.22)	0.76 (0.45 to 1.28)	-	-
6 mo	0.70 (0.46 to 1.07)	0.64 (0.39 to 1.06)	-	-

mo – months

*Adjusted for socioeconomic status at birth, maternal schooling, skin colour, maternal age, smoking during pregnancy, birthweight, subject's age at follow-up, and sex.

†Adjusted for maternal age, maternal education, residence, main income, and fridge ownership (all measured at birth) and child age, child sex, birth order, birth weight, HIV exposure.