Number of siblings, birth order, and childhood overweight: a population-based cross-sectional study in Japan

BMC Public Health

Table 3 Crude and adjusted odds ratios of number of siblings and birth order for overweight

Variables	Total N	Overweight n (%)	Crude		Adjusted^a
			OR	95% CI	OR	95% CI
Number of siblings (%)
0 (only child)	423	95 (22.5)	1.00		1.00
1	2215	360 (16.3)	0.67	0.52-0.86	0.62	0.46-0.83
2 or more	1388	201 (14.5)	0.59	0.45-0.77	0.50	0.36-0.68
			P for trend < 0.001		P for trend < 0.001
Birth order (%)
Only child	423	95 (22.5)	1.82	1.29-2.55	2.13	1.45-3.14
Oldest child	1617	230 (14.2)	1.04	0.78-1.39	1.01	0.73-1.40
Youngest child	1477	261 (17.7)	1.35	1.01-1.79	1.56	1.13-2.16
Middle child	509	70 (13.8)	1.00		1.00

OR; odds ratio; CI: confidence interval.
^aAdjusted for sex, birth weight, eating speed, exercise, sleeping hours, mother’s age, paternal overweight, and maternal overweight.

ISSN: 1471-2458