Excessive screen time stunts child growth
Excessive screen time in young children may stunt their development, resulting in poorer performance in developmental screening tests, according to a new study.
In the relationship between technology and development, “[r]esults suggest that screen time is likely the initial factor: greater screen time at 24 months was associated with poorer performance on developmental screening test sat 36 months, and similarly, greater screen time at 36 months was associated with lower scores on developmental screening tests at 60 months. The obverse association was not observed,” said researchers.
In a 3-wave, longitudinal cohort study, 2,441 mothers (mean age at enrolment, 30.60±4.55 years) reported that their children (47.9 percent male) viewed screens at a weekly mean of 17.09±11.99 hours at 24 months, 24.99±12.97 hours at 36 months and 10.85±5.33 hours at 60 months. [JAMA Pediatr 2019;doi:10.1001/jamapediatrics.2018.5056]
The corresponding mean Ages and Stages Questionnaire, Third Edition (ASQ-3) scores at 24, 36 and 60 months were 51.25±6.50, 52.67±6.38 and 54.93±5.52.
Using a random-intercepts, cross-lagged panel model, researchers found that heighted exposure to screens at 24 months correlated with significantly lower developmental screening scores at 36 months (β, –0.08; 95 percent CI, –0.13 to –0.02). Screen time at 36 months was also linked to lower developmental scores at 60 months (β, –0.06; –0.13 to –0.02).
The opposite-direction relationship was not significant, such that lower scores on developmental tests were not associated with screen time at a later time point. Within-time covariances were also null.
“Taken together, these findings suggest that higher levels of screen exposure relative to a child’s average level of screen time were associated with significantly poorer performance on developmental screening tests at the next study wave relative to a child’s average level of developmental milestones,” said researchers.
Multivariate regression analysis additionally demonstrated that girls (β, 0.23; 0.18–0.27) tended to score higher on the ASQ-3, as did children who were born to mothers with low maternal depression (β, –0.06; –0.11 to –0.01) and who were exposed to reading (β, 0.12; 0.06–0.18). The same factors predicted lower screen time (female sex: β, –0.06; –0.11 to –0.02; maternal depression, β, 0.08; 0.03–0.13; reading: β, –0.08; –0.013 to –0.02).
“Taken together, these findings suggest that many factors may influence a child’s propensity for excessive screen time. It is possible, however, that not all children are equally and putatively influenced by screen time,” said researchers, explaining that some of the above factors may serve as buffers to the negative effects of screen time on child development.
Nevertheless, several important implications and recommendations can be drawn from the present findings, they continued. Practitioners should emphasize to parents the potential harms of excessive screen times and help them personalized media plans.
“Media plans can be customized to help meet each family’s needs,” researchers added. “The plans provide guidance on setting and enforcing rules and boundaries regarding media use based on child age, how to devise screen-free zones and device curfews in the home, and how to balance and allocate time for online and offline activities to ensure that physical activity and family interactions are prioritized.”