Table 4.

Summary regression results for age trends for any breastfeeding

Stratum name	Stratum characteristics	Intercept (95% confidence interval)	Slope (95% confidence interval)	Standard error of the residual
AfrD	Africa: high adult, high child mortality	4.28 (4.05, 4.51)	-0.20 (-0.21, -0.19)	1.30
AfrE	Africa: very high adult, high child mortality	4.71 (4.43, 5.00)	-0.20 (-0.21, -0.18)	1.12
AmrB	Americas: low child, low adult mortality	1.34 (1.16, 1.52)	-0.12 (-0.13, -0.11)	0.79
AmrD	Americas: high adult, high child mortality	3.57 (3.29, 3.86)	-0.18 (-0.20, -0.17)	0.83
EmrB	Eastern Mediterranean: low child, low adult mortality	2.85 (2.58, 3.12)	-0.22 (-0.23, -0.20)	0.36
EmrD	Eastern Mediterranean: high adult, high child mortality	3.40 (3.16, 3.64)	-0.17 (-0.18, -0.16)	0.80
SearB	South-east Asia: low child, low adult mortality	3.58 (3.36, 3.79)	-0.14 (-0.15, -0.13)	0.49
SearD	South-east Asia: high adult, high child mortality	4.03 (3.72, 4.34)	-0.14 (-0.15, -0.12)	0.89
WprB	Western Pacific: low child, low adult mortality	2.18 (1.77, 2.60)	-0.14 (-0.16, -0.12)	2.77

Regressions use minimum chi-square estimation with dependent variable logarithm of prevalence odds (that is, Log(p/1 - p), where p is prevalence of any breastfeeding), and independent variable oldest month of age by two-month age groups; regressions for category-A countries stratified by geographical and epidemiologic criteria as noted in the table; any breastfeeding estimated for 18 age groups 0–1 to 34–35 months of age. Data sources listed in the Annex (Additional file 1).