Table 2.

Family characteristics of study participants by the number of siblings

Variables	None (only child)		One		Two or more		Total		χ2	P valuea
	N	%	N	%	N	%	N	%
Father’s weight status									19.60	0.001
Underweight	1594	3.25	203	2.96	288	2.48	2085	3.09
Normal	30,935	63.01	4353	63.53	7394	63.60	42,682	63.16
Overweight	12,667	25.80	1788	26.09	2946	25.34	17,401	25.75
Missing	3901	7.95	508	7.41	997	8.58	5406	8.00
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00
Father’s education level									10,349.70	< 0.001
Low	8524	17.36	2416	35.26	7275	62.58	18,215	26.96
Middle	22,081	44.97	2386	34.82	3137	26.98	27,604	40.85
High	18,292	37.26	2023	29.52	1162	10.00	21,477	31.78
Missing	200	0.41	27	0.39	51	0.44	278	0.41
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00
Mother’s weight status									509.04	< 0.001
Underweight	5260	10.71	579	8.45	726	6.25	6565	9.72
Normal	35,611	72.53	4982	72.71	8193	70.48	48,786	72.20
Overweight	4794	9.76	840	12.26	1807	15.54	7441	11.01
Missing	3432	6.99	451	6.58	899	7.73	4782	7.08
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00
Mother’s education level									12,096.00	< 0.001
Low	9842	20.05	2691	39.27	8306	71.45	20,839	30.84
Middle	22,742	46.32	2511	36.65	2475	21.29	27,728	41.03
High	16,450	33.51	1632	23.82	823	7.08	18,905	27.98
Missing	63	0.13	18	0.26	21	0.18	102	0.15
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00
Family income									3362.13	< 0.001
Low	10,257	20.89	1828	26.68	5368	46.18	17,453	25.83
Middle	29,251	59.58	3322	48.48	4862	41.82	37,435	55.40
High	9563	19.48	1694	24.72	1388	11.94	12,645	18.71
Missing	26	0.05	8	0.12	7	0.06	41	0.06
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00
Residential site									1241.61	< 0.001
Suburban	36,765	74.88	5567	81.25	10,421	89.64	52,753	78.07
Urban	12,313	25.08	1284	18.74	1200	10.32	14,797	21.90
Missing	19	0.04	1	0.01	4	0.03	24	0.04
Total	49,097	100.00	6852	100.00	11,625	100.00	67,574	100.00

^aP Value from Chi-squared test