Characteristics of included studies
| Author | Age | Outcome measures | Meta-analysis | Studies (n, CS, LS, RCT, N of subjects) | % duplicate studies | Narrative findings | Findings of meta-analysis |
| Pearson and Biddle19 | C< 11 y; A: 12–18 y | Dietary intake; assessed largely through food frequency questionnaires | No | n=53; 19 in C and 26 in Ad; largely CS; 5 LS in C and 5 LS in Ad. Total N not reported. | 14.6% | C (<12 y): TVST – assoc. with fruit, vegetable consumption; + assoc. with energy-dense snack consumption, fast food consumption, energy-dense drinks, total energy intake, percentage energy from fat. Ad: ST – assoc. with fruit, vegetable, FV, fibre consumption; + assoc. energy-dense snack, fast food, fried food consumption, energy dense drink, total energy intake, percentage energy from fat, total fat. | C: strengths of assoc. were mainly small to moderate (no exact values given); Ad: strength of assoc. was small to moderate for energy-dense drinks and snacks (no exact values given). |
| LeBlanc et al 18 | 0–4 y | Adiposity (n=11), psychosocial health (n=6), cognitive development (n=8 studies). No studies identified of bone mass, motor development or cardiometabolic health | No | n=23. N=22 417. | 13.0% | Infants: TVST elicited no benefits and may be harmful to cognitive development; increased TVST assoc. with unfavourable adiposity. Toddlers: TVST has – impact on adiposity, cognitive development, – affected psychosocial health Preschoolers: TVST – impact on adiposity; evidence between increased TV and decreases scores on measures of psychosocial health; – relationship between TVV and cognitive development | |
| Costigan et al 8 | 12–18 y | Physical, psychosocial and/or behavioural health outcomes | No | n=33; 25 CS, 8 LS. | 21.2% | ST + assoc. with weight status, neck/shoulder/lower back pain, backache/headache, sleep problems and depressive symptoms; − assoc. with perceived health and healthy dietary behaviour. | |
| Tremblay et al 10 | 5–17 y | Body composition, physical fitness, metabolic syndrome (MetS), cardiovascular risk, self-esteem, prosocial behaviour, academic performance | Yes | n=232; 8 RCTs, 10 intervention studies, 37 LS and 177 CS. N= 983 840. | 2.2% | +assoc. between adiposity and TVST; assoc. between ST and higher cholesterol and blood pressure, haemoglobin A1c and insulin insensitivity; − relationship between ST and self-esteem; >2 hours/day ST assoc. with lower cardiorespiratory fitness. | TVST and BMI was the only area where data allowed meta-analysis; 4 RCTs included in the meta-analysis: decreased TVST assoc. with decrease in BMI (−0.89 kg/m2 (95% CI −1.467 to −0.11, p=0.01). |
| Suchert et al 10 | 5–18 y | Depressive symptoms, anxiety symptoms, internalising problems, self-esteem, eating disorder symptoms, hyperactivity and inattention problems, well-being and quality of life (QoL) | No | n=91; 73 CS, 16 LS, 2 RCT. N not reported. | 7.7% | + assoc. between ST and hyperactivity/inattention problems, internalising problems, poorer psychological well-being and perceived QoL. Indeterminate assoc. between SBB and depressive and anxiety symptoms, self-esteem and eating disorder symptoms. | |
| van Ekris et al 11 | <18 y | Anthropometrics, cardiometabolic risk, blood pressure, fitness, other biomedical health indicators | Yes | n=109; N=24 257 for MA of TVV and BMI from 9 prospective cohorts. N=6971 for MA of computer screen viewing and BMI from 5 prospective cohorts. | 5.2% | + relationship between TVST and overweight/obesity incidence and overweight/obesity incidence; NoE for relationship between computer use/game time with BMI/BMI z-score or WC/WC z-score; + relationship between ST and BMI/BMI z-score and overweight/obesity. NoE for relationship between ST and triglycerides and glucose, low-density lipoprotein cholesterol, ratio of total cholesterol to high-density lipoprotein cholesterol and systolic and diastolic blood pressure; - relationship between TVST and cardiorespiratory fitness/VO2max; InE with strength and being unfit, cardiorespiratory fitness/VO2max and metabolic risk z-scores, asthma and bone mass indicators. | MA: BMI at follow-up was not significantly associated with each additional hour of TV viewing (β=0.01, 95% CI (−0.002 to 0.02)) or computer use (β=0.00, 95% CI (-0.004 to 0.01)) per day, with high heterogeneity in each analysis. Adjustment for physical activity or diet did not change findings. |
| Carson et al 17 | 5–17 y | Body composition, MetS/cardiovascular disease risk factors, academic achievement, fitness, self-esteem | No | n=235; 1 RCT, 1 cross-over trial, 49 LS, 5 CC and 179 CS. 35 used accelerometer measures of SB. N not stated. | 3.5% | Higher ST assoc. with unfavourable body composition, overweight/obese and with clustered risk factor score and lower cardiorespiratory fitness, unfavourable measures of behaviour, lower self-esteem (TVST); inconsistent findings for assoc. with lower academic attainment. | |
| Hoare et al 20 | 10–19 y | Depressive symptomatology, anxiety symptomatology, self-esteem, suicide ideation, other mental health indicators | No | n=32; 1 RCT, 6 LS, 24 CS. | 21.9% | + Relationship between ST and depressive symptomatology, psychological distress and ST duration and severity of anxiety symptoms. + Relationship between low self-esteem and screen time. InE for relationship between ST and suicidal ideation. | |
| Duch et al 9 | <3 y | Biological and demographic factors, family biological and demographic factors, family structure factors, behavioural factors, structural environmental factors | No | n=29; 18 CS, 10 LS, 1 RCT. N not stated. | 3.5% | + Assoc. between ST and age and BMI. InE on ST and sleep duration and crying duration. | |
| Marsh et al 1 | 5–24 y | Energy intake measured objectively in experimental studies using an experimental meal during two exposure scenarios | No | n=10; 8 RCT and 2 quasi-experimental studies. | 0 | ST (in the absence of food advertising) assoc. with increased dietary intake; TVST increases intake of very palpable energy-dense foods; stimulatory effects of TVST on intake were stronger in overweight/obese C than those of normal weight | |
| Hale and Guan24 | 5–17 y | Sleep outcomes | No | n=67; 3 RCT. | 0 | Assoc. with at least one of the sleep outcomes (delayed bedtime, shortened total sleep time, daytime tiredness, sleep onset latency) was found for computer use, video gaming, mobile device, unspecified ST. | |
| Goncalves de Oliveira et al 23 | 10–19 y | MetS | Yes. ST dichotomised as ≤2 h vs >2 h for analyses | n=21; 9 examined ST, 8 CS, 1 CC. N=8680. | 0 | Inconclusive evidence for the assoc. of ST or TVST with presence of the MetS. | Significant assoc. was not identified between ST and MetS; OR for MetS in relation to >2 h ST=1.20 (95% CI 0.91 to 1.59), p=0.20, n=3881, studies =6, I2=37%). Subgroup analysis: no significant assoc. between ST and MetS through the whole week (OR=1.03 (95% CI 0.75 to 1.42), p=0.84, n=2261, studies=4, I2=24%); however, there was a significant assoc. between weekend ST and MetS (OR=2.05 (95% CI 1.13 to 3.73), p=0.02, n=1620 studies=2, I2=0%). |
| Wu et al 22 | 3–18 y | Health-related quality of life (HRQOL) | Yes. ST dichotomised as <2–2.4 h vs ≥2–2.5 h | n=31, 17 examined ST. 13 CS, 1 LS. Total N not reported. | Assoc. of ST with with HRQOL, consistent across television, computer and video screentime and across CSS and LS. 1 IS reported a dose-response relationship between screentime and HRQOL. HRQOL was lower across physical, mental and psychosocial health, school functioning, and general health domains. | Significant assoc. between higher screentime and lower HRQOL: >2–2.5 h/day ST associated with fall in HRQOL by 2.71 (1.59, 3.38; studies=2). |
+ or – used for direction of association of screentime (ST) with health outcomes. n refers to studies while N refers to total number of participants across the reviews. Per cent duplicate studies refers to the proportion of studies within a review that were included in any other included review.
assoc., associated with; Ad, adolescent; BMI, body mass index; C, child; CC, case-control study; CS, cross-sectional study; FV, fruit and vegetable; MA, meta-analysis; NoE, no evidence; RCT, randomised controlled trial; LS, longitudinal study; QOL, quality of life; ST, screentime; TST, total sleep time; TVST, television screentime; y, year.