Table 1.

Maternal and Childhood Characteristics by Childhood Total Sleep Duration and Sleep Disturbance (n, %)

Variables	Total		Childhood Sleep Duration (9.37±1.30)						Childhood Sleep Disturbance (52.49±7.88)
			≥10 h		<10 h		χ2/t	p value	CSHQ≤41		CSHQ>41		χ2/t	p value
	n	%	N=2150	34.50%	N=4086	65.50%			N=362	5.80%	N=5874	94.19%
Maternal Characteristics
Maternal age at delivery							0.502	0.778					7.034	0.03
<25	933	15.18%	323	15.24%	610	15.14%			63	17.55%	870	15.03%
25–34	4699	76.43%	1612	76.04%	3087	76.64%			255	71.03%	4444	76.77%
≥35	516	8.39%	185	8.73%	331	8.22%			41	11.42%	475	8.21%
Maternal education level							4.127	0.127					3.678	0.159
Less than high school	588	9.43%	184	8.56%	404	9.89%			38	10.50%	550	9.36%
High school	963	15.44%	350	16.28%	613	15.00%			67	18.51%	896	15.25%
College and above	4685	75.13%	1616	75.16%	3069	75.11%			257	70.99%	4428	75.38%
Overweight/obesity before pregnancy							1.865	0.172					1.025	0.311
Yes	595	9.56%	190	8.86%	405	9.93%			40	11.08%	555	9.47%
No	5629	90.44%	1955	91.14%	3674	90.07%			321	88.92%	5308	90.53%
Family structure							4.816	0.09					14.269	0.001
Nuclear family	3561	57.10%	1268	58.98%	2293	56.12%			241	66.57%	3320	56.52%
Single-parent family	170	2.73%	54	2.51%	116	2.84%			9	2.49%	161	2.74%
Large family	2505	40.17%	828	38.51%	1677	41.04%			112	30.94%	2393	40.74%
Family income (RMB (yuan)/month/person)							6.961	0.031					2.711	0.258
<3999	667	10.70%	220	10.23%	447	10.94%			48	13.26%	619	10.54%
4000–7999	2345	37.60%	769	35.77%	1576	38.57%			130	35.91%	2215	37.71%
>8000	3224	51.70%	1161	54.00%	2063	50.49%			184	50.83%	3040	51.75%
Smoking during pregnancy							0.265	0.607					0.441	0.507
Yes	134	2.15%	49	2.28%	85	2.08%			6	1.66%	128	2.18%
No	6102	97.85%	2101	97.72%	4001	97.92%			356	98.34%	5746	97.82%
Alcohol use during pregnancy							0.002	0.966					0.434	0.51
Yes	153	2.45%	53	2.47%	100	2.45%			7	1.88%	136	2.32%
No	6083	97.55%	2097	97.53%	3986	97.55%			365	98.12%	5728	97.68%
Physical activity during pregnancy							2.337	0.126					8.955	0.003
≥2 h	2373	38.05%	846	39.35%	1527	37.37%			614	13.31%	265	16.32%
<2 h	3863	61.95%	1304	60.65%	2559	62.63%			3998	86.69%	1359	83.68%
Stressful life event							0.051	0.822					0.428	0.513
Yes	266	4.30%	90	4.20%	176	4.30%			13	3.60%	253	4.30%
No	5970	95.70%	2060	95.80%	4086	95.70%			349	96.40%	5621	95.70%
Family history of sleep disorders							0.869	0.351					33.502	<0.001
Yes	1637	26.25%	549	25.53%	1088	26.63%			48	13.26%	1589	27.05%
No	4599	73.75%	1601	74.47%	2998	73.37%			314	86.74%	4285	72.95%
Childhood Characteristics
Age (mean, SD)	5.16	0.88	4.9943	0.87	5.2446	0.87	10.733	<0.001	5.39	0.89	5.14	0.88	−5.271	<0.001
Gender							2.908	0.088					3.04	0.081
Boys	3289	52.74%	1102	51.26%	2187	53.52%			207	57.18%	3082	52.47%
Girls	2947	47.26%	1048	48.74%	1899	46.48%			155	42.82%	2792	47.53%
Obesity/overweight							8.93	0.003					1.664	0.197
Yes	1135	18.28%	348	16.26%	787	19.35%			75	20.83%	1060	18.13%
No	5073	81.72%	1792	83.74%	3281	80.65%			285	79.17%	4788	81.87%
Allergic disease							0.123	0.726					76.712	<0.001
Yes	3485	55.89%	1195	55.58%	2290	56.05%			122	33.70%	3363	57.25%
No	2751	44.11%	955	44.42%	1796	43.95%			240	66.30%	2511	42.75%
ADHD							0.158	0.691					3.386	0.66
Yes	99	1.59%	36	1.67%	63	1.54%			1	0.28%	98	1.67%
No	6137	98.41%	2114	98.33%	4023	98.46%			361	99.72%	5776	98.33%
Physical activity							30.585	<0.001					32.021	<0.001
≥1 h	2675	42.90%	1025	47.67%	1650	40.38%			207	57.18%	2468	42.02%
<1 h	3561	57.10%	1125	52.33%	2436	59.62%			155	42.82%	3406	57.98%
Screen exposure							2.697	0.101					9.194	0.002
≥1 h	2273	36.45%	754	35.07%	1519	37.18%			105	29.01%	2168	36.91%
<1 h	3963	63.55%	1396	64.93%	2567	62.82%			257	70.99%	3706	63.09%

Note: Bold values indicate statistical significance.

Abbreviations: ADHD, attention deficit hyperactivity disorder; CSHQ, children’s sleep habits questionnaire; SD, standard deviation.