The Impact of Problematic Smartphone Use on Sleep Quality Among Chinese Young Adults: Investigating Anxiety and Depression as Mediators in a Three-Wave Longitudinal Study

Figures & data

Table 1 The Basic Demographic Characteristics of the Study Subjects (n=2993)

Characteristics	n(%)	Characteristics	n(%)
Sex		Relationships with families
Male	1007 (34.3)	Better	2634 (89.8)
Female	1926 (65.7)	Average	244 (8.3)
		Poor	55 (1.9)
Age(years), M±SD	2993 (19.7±1.2)
Ethnicity		Relationships with classmates
Han	1267 (43.2)	Better	2467 (84.1)
Tibetan	1583 (54.0)	Average	437 (14.9)
Others	83 (2.8)	Poor	29 (1.0)
Place of origin		Relationships with teachers
Urban	852 (29.0)	Better	2046 (69.8)
Rural	2081 (71.0)	Average	864 (29.5)
		Poor	23 (0.8)
Family economic status		Smoked
Better	478 (16.3)	Yes	304 (10.2)
Average	1540 (52.5)	No	2629 (87.8)
Poor	915 (31.2)
Academic stress		Drank alcohol
Minor	454 (15.5)	Yes	391 (13.1)
Moderate	1160 (39.5)	No	2542 (86.9)
Major	1319 (45.0)
Parents’ marital status
Harmonious	1686 (57.5)
Sometimes, frequent quarrels	929 (31.7)
Separated, divorced	184 (6.3)
Other	134 (4.6)

Abbreviation: M±SD, Mean ± Standard Deviation.

Table 2 Variable Correlation Analysis

Variable	1	2	3	4
1.T1 PSU	1
2.T2 Anxiety symptoms	0.20***	1
3.T2 Depressive symptoms	0.23***	0.76***	1
4.T3 Sleep quality	0.16***	0.34***	0.39***	1

Note: ***P<0.001.

Abbreviation: PSU, problematic smartphone use.

Figure 1 The chain mediating pathway of T2 anxiety and depressive symptoms on T1 PSU and T3 sleep quality; The model corrected for baseline factors like sex, age, place of origin, family economic status, ethnicity, academic pressure, parents’ marital status, the respondents’ relationships with their families, classmates, and teachers, smoked and drank alcohol consumption; ***P<0.001, **P<0.01, *P<0.05.

Abbreviation: PSU, problematic smartphone use.

Table 3 The Effect of T1 PSU on T3 Sleep Quality: Serial Mediating Effects of T2 Anxiety and Depressive Symptoms (n=1807)^a

	T2: Anxiety Symptoms			T2: Depressive Symptoms			T3: Sleep Quality
	β	SE	95% CI	β	SE	95% CI	β	SE	95% CI
T1: PSU	0.055	0.008	0.039–0.070	0.024	0.006	0.012–0.035	0.021	0.006	0.010–0.033
T2: Anxiety symptoms				0.857	0.017	0.824–0.889	0.060	0.026	0.008–0.112
T2: Depressive symptoms							0.160	0.024	0.113–0.206
	R^2=0.047			R^2=0.619			R^2=0.132
	F=9.760***			F=291.153***			F=9.002***
						Effect size	SE	95% CI	Relative mediation (%)
Total effect						0.036	0.006	0.024–0.048	100.0
Direct effect						0.021	0.006	0.010–0.033	58.3
Indirect effect						0.015	0.002	0.011–0.019	41.7
T1 PSU -T2 Anxiety symptoms -T3 Sleep quality (ind1)						0.003	0.002	0.000–0.006	20.0
T1 PSU -T2 Depressive symptoms -T3 Sleep quality (ind2)						0.004	0.001	0.002–0.006	26.7
T1 PSU -T2 Anxiety symptoms -T2 Depressive symptoms -T3 Sleep quality (ind3)						0.008	0.002	0.005–0.011	53.3
Comparison one (ind1-ind2)						−0.002	0.008	−0.018–0.014	–
Comparison two (ind1-ind3)						−0.163	0.010	−0.038–0.002	–
Comparison three (ind2-ind3)						−0.143	0.007	−0.028--0.003	–

Notes: ^aThe model excluded students with poor sleep quality in T1 and T2 and students with anxiety and depression symptoms in T1 from the original data; The model corrected for baseline factors like sex, age, place of origin, family economic status, ethnicity, academic pressure, parents’ marital status, the respondents’ relationships with their families, classmates, and teachers, smoked and drank alcohol consumption; ***P<0.001.

Abbreviations: PSU, problematic smartphone use; ind, indirect.