Sleep disturbance and internalizing symptoms in adolescents: a moderated mediation model of self-control and mindfulness

Table 1 Descriptive statistics of the overall sample (n = 1876)

		n	%
Age ^a [year, mean(SD)]	14.88 (1.47)	-	-
Gender	Boys	838	44.7
Gender	Girls	1038	55.3
Grade [age]	7th [13.42 (0.72)]	569	30.3
	8th [14.35 (0.73)]	562	30.0
	10th [15.95 (0.59)]	387	20.6
	11th [16.86 (0.60)]	358	19.1
Ethnicity	Han ^b	1858	99.0
Ethnicity	Others	18	1.0
Parental martial status	Married	1754	93.5
Parental martial status	Not current married ^c	122	6.5
Immigrants’ second generation	Yes	155	8.3
Single child status	Yes	131	7.0
Left-behind status ^d	Yes	231	12.3
Father has a stable job	Yes	1593	84.9
Mother has a stable job	Yes	1382	73.7
Self history of psychiatric illness	Yes	9	0.5
Chronic physical illness ^e	Yes	106	5.7
Family history of psychiatric illness	Yes	11	0.6
Local resident	Yes	1520	81.0
Local resident	No	356	19.0
Family incomes	< 5000	446	23.8
	5000–10,000	666	35.5
	10,000–20,000	174	9.3
	> 20,000	43	2.3
	Unknown	547	29.2
Father’s educational level	Illiteracy	280	14.9
	Elementary school	986	52.6
	Junior high school	398	21.2
	Senior high school	136	7.2
	Junior college	73	3.9
	College	3	0.2
Mother’s educational level	Illiteracy	480	25.6
	Elementary school	908	48.4
	Junior high school	357	19.0
	Senior high school	88	4.7
	Junior college	40	2.1
	College	3	0.2
Degree of impact by COVID-19 on life	No impact	485	25.9
	Minimal impact	660	35.2
	Moderate impact	554	29.5
	Significant impact	149	7.9
	Very significant impact	28	1.5
Alcohol intake	Never	1718	91.6
	Sometime	154	8.2
	Often	4	0.2
	Everyday	0	0.0
Exercise	Never	96	5.1
	Sometime	1187	63.3
	Often	438	23.3
	Everyday	155	8.3
Smoking	Never	1844	98.3
	Sometime	19	1.0
	Often	1	0.1
	Everyday	5	0.3
	Quit smoking	7	0.4

Note
^a The range of age in the current sample was 12–19
^b Han is the major ethnic group in China
^c Not current married included separated, divorced, and widowed
^d Live separately from one or both parents for more than 6 months
^e Chronic physical conditions referred to having at least one of arthritis angina, asthma, diabetes, visual impairment, or hearing problems

ISSN: 1471-244X