|Type of Study||Number of Studies||Number of participants||Narrative recommendation and main findings|
|Longitudinal||3||3530||Watching > 1 hr of TV per day is associated with attention difficulties.|
|Cross sectional||32||157637||> 2 hrs of screen time per day resulted in lower academic achievement.|
|Total of all studies||35||161167||
> 2 hrs of screen time per day is negatively associated with academic achievement.|
Dose-response relation between time spent playing video games, watching TV and using the computer (for non-academic purposes). > 3 hrs/day associated with poor school performance and lower I.Q. scores.
Mean Downs and Black score = 19.1 (± 2.1), Level 3 evidence.