TABLE 1.

Characteristics of included studies in the meta-analysis.

First author	Study name	Country	Sample size	Age at baseline (years)	Gender	Study period	Screen equipment	Depression measurement	Depression at baseline	Follow-up time (months)	Covariates adjustment
Primack et al. (41)	Add Health	America	4,142	Mean 21.8 ± 1.82	M/F	General	TV, videocassettes, computer games	CES-D	Excluded	84	Sex, age, race, ethnicity, maternal educational level, the participants’ marital status and highest level of educational attainment at follow-up
Lucas et al. (46)	the Nurses’ Health Study	USA	49,821	Range 30–55	F	General	TV	Both depression diagnosis and use of antidepressants	Excluded	120	Age, time interval, current postmenopausal hormonal use, body mass index, marital status, involvement in a social or community group, smoking status, total energy intake, coffee intake, reported diagnosis of diabetes mellitus, cancer, myocardial infarction or angina, high blood pressure, rheumatoid arthritis, osteoarthritis, asthma, emphysema, categories of television watching, categories of physical activity, physical limitations in 1992, five-item Mental Health Index score in 1992
Thomée et al. (44)	None	Sweden	4,156	Range 20–24	M/F	General	Mobile phone	Two items from Prime-MD	Excluded	12	Relationship status, educational level, and occupation
Thomée et al. (45)	None	Sweden	4,163	Range 20–24	M/F	General	Computer	Two items from Prime-MD	Excluded	12	Relationship status, educational level, and occupation
Grøntved et al. (51)	EYHS	Danish	435	Mean 15.6 ± 0.4	M/F	General	TV and computer	MDI	Excluded	144	Age at baseline, follow-up time, sex, parental education level, parental marital status, smoking status, and alcohol intake in adolescence, and with school id treated as a random effect, BMI in adolescence, cardiorespiratory fitness in adolescence
Sui et al. (38)	ACLS	America	4,802	Range 18–80; mean 48.4 ± 9.8	M/F	General	TV	CES-D	Excluded	464	Age, gender, education, marital status, employment status, current smoker, body mass index, diabetes, and MVPA (hours/week)
Padmapriya et al. (43)	GUSTO	Asia	1,144	Mean 30.7 ± 5.1	F	During pregnancy	TV	EPDS	Included	17	Age, education, working during pregnancy, household income, smoking history, parity during pregnancy, and pregnancy BMI
Wu et al. (39)		China	2,521	Mean 18.43 ± 0.96	M/F	General	Video; computer, TV/video programs	CES-D	Included	14	Sex, age, residential background, BMI, perceived family economy, sleep quality, smoking, alcohol intake, exercise after school and physical activity
Khouja et al. (40)	the Avon Longitudinal Study of Parents and Children, a UK-based prospective cohort study	UK	1,869	16	M/F	General	TV, computer, texting	CIS-R	Included	24	Sex, maternal age, anxiety at age 15, maternal anxiety and depression, maternal education, parental socioeconomic position, also adjusted for child IQ, parental conflict, presence of the child’s father, number of people living in the child’s home, bullying and family TV use in early life, time spent alone (weekdays or weekends, as applicable)
Liu et al. (37)		China	3,396	Range 14–24; mean 18.3 ± 1.7	M/F	General	Mobile phone	BDI	Excluded	8	Age, sex, and other sociodemographics with significant associations with LTMPU at baseline; lifestyle practice and health conditions with significant associations with LTMPU at baseline
Zink et al. (42)	H&H	USA	2,525	Range 13–16; mean 14.6	M/F	General	TV, computer/ videogame	RCADS	Included	12	Demographic characteristics of sex, age, race, ethnicity, and highest parental education, SES, BMI percentile based on self-reported height and weight using the age- and sex-normed CDC standardized guideline, baseline Major Depressive Disorder, baseline computer/videogame use, baseline television viewing
Choi et al. (49)	Phenotypic and genomic data from over 100,000 UK Biobank participants	British	100,517	Range 18+	M/F	General	TV, computer	PHQ-9	Excluded	96	Participant characteristics (sex, age, assessment center), sociodemographic factors (socioeconomic deprivation, employment status, household income, completion of higher education, urbanicity, household size), and physical health factors (BMI and reported physical illness or disability)
Meyer et al. (48)	the COVID-19 and Well-being Study	USA	2,327	Range 18+	M/F	During COVID-19 pandemic	Screen not specific	BDI	Included	2	Age and sex, public health guidelines, time point (nine time points; weeks 0–8), and the interaction of time with each factor
Sarris et al. (35)	the UK Biobank	UK	31,343	Range 37–73; mean 56.7 ± 8.1	M/F	General	TV, computer	An item from PHQ-9	Excluded	120	Age, gender, ethnicity, social deprivation, education, and BMI
Ayuso-Mateos et al. (52)	the Edad con Salud project	Spain	1,103	Range 18+ mean 54.8 ± 16.4	M/F	During COVID-19 pandemic	Screen not specific	CIDI	Excluded	2	Age, sex, education level, whether the participant lived alone (both before and during the lockdown), whether the participant had co-habited/was co-habiting with a relative isolated by COVID-19, whether the participant had been/was concerned about a relative/friend infected by COVID-19, whether the participant had been infected with COVID-19 and its severity, whether the participant had enough quietness at home to get proper rest, whether the house-hold economic situation had worsened due to the COVID-19 emergency, whether the participant had been unemployed due to the COVID-19 emergency, time a day spent in front of screens during the lockdown (working and non-working), pre- and post-measure levels of physical activity
Kandola et al. (47)	the Millennium Cohort Study	UK	7,701	11	M/F	General	Video games, social media and leisure-time internet use	sMFQ	Included	36	Gender, socioeconomic position (household income), baseline emotional symptoms, self-reported maternal history of a depression or anxiety diagnosis, the self-reported experience of bullying, self-reported physical activity, and standardized, BMI
Liu et al. (36)	MABC	China	2,490	0	M/F	General	TV, electronic products (mobile phones, tablets, computers and others)	SDQ	Excluded	48	Age, gender, number of siblings, delivery model, birth weight, maximum educational level of parents, family income, passive smoking, outdoor activities
Pimenta et al. (50)	the SUN Project	Spanish	12,691	Mean 36.7 ± 11.5	M/F	General	TV, computer	DSM-IV	Excluded	21	Gender, marital status, years of university education, working hours, living status, hanging out with friends, smoking, physical activity, total energy intake, Mediterranean diet score, baseline self-perception of competitiveness, anxiety, and dependence levels, baseline BMI, use of tranquilizers or anxiolytics, insomnia, sleeping hours

USA, the United States; UK, the United Kingdom; F, female; M, male; Add Health, the National Longitudinal Survey of Adolescent Health; EYHS, the Danish cohorts of the European Youth Heart Study; ACLS, Aerobics Center Longitudinal Study; GUSTO, the growing up in Singapore toward healthy outcomes; H&H, the Happiness and Health study; MABC, the Ma’anshan Birth Cohort prospective cohort study; SUN, the “Seguimiento Universidad de Navarra” project; TV, television; CES-D, the Center for Epidemiological Studies Depression scale; Prime-MD, Primary care evaluation of mental disorders; MDI, the Major Depression Inventory; EPDS, the Edinburgh Postnatal Depression Scale; CIS-R, self-administered, computerized version of the revised Clinical Interview Schedule; BDI, the Beck Depression Inventory; RCADS, the Revised Children’s Anxiety and Depression Scale; PHQ-9, the Patient Health Questionnaire-9; CIDI, the Chinese version of the computerized Composite International Diagnostic Inventory; sMFQ, short Moods and Feelings Questionnaire; SDQ, the Strengths and Difficulties Questionnaire; DSM-IV, the Diagnostic and Statistical Manual of Mental Disorders; BMI, body mass index; SES, socioeconomic status; MVPA, moderate and vigorous physical activity; LTMPU, long-time mobile phone use; CDC, the Centers for Disease Control and Prevention; SES, socioeconomic status; COVID-19, coronavirus disease 2019; IQ, intelligence quotient.