Table 5.

Estimated parameters for mediation multilevel models, as schematized in Fig. 1c, assessing the effect of screen time on impulsivity through neuropsychological functions.

Predictors	Mediators
	Response inhibition				Working memory
	Estimate	Std. Er	Pr( >|t|)	95% CI	Estimate	Std. Er	Pr( >|t|)	95% CI
Social media use predicting impulsivity through the mediator
Between-person	0.041	0.014	0.000	0.016, 0.070	0.040	0.011	0.000	0.020, 0.066
Within-person	0.002	0.001	0.005	0.000, 0.005*	0.001	0.001	0.025	0.000, 0.002
Lagged-within-person	0.000	0.001	0.420	− 0.002, 0.001	0.001	0.001	0.090	0.000, 0.002
Television viewing predicting impulsivity through the mediator
Between-person	0.028	0.011	0.000	0.011, 0.053	0.026	0.010	0.000	0.009, 0.046
Within-person	0.000	0.001	0.473	− 0.002, 0.002	0.001	0.001	0.045	0.000, 0.002
Lagged-within-person	0.000	0.001	0.423	− 0.001, 0.001	0.000	0.001	0.385	− 0.002, 0.001
Video gaming predicting impulsivity through the mediator
Between-person	0.017	0.009	0.003	0.002, 0.036	0.037	0.010	0.000	0.017, 0.056
Within-person	0.001	0.001	0.073	0.000, 0.003	0.000	0.000	0.260	− 0.001, 0.001
Lagged-within-person	0.000	0.000	0.473	− 0.001, 0.001	0.000	0.001	0.130	− 0.002, 0.000

The significant between- and within-person associations are highlighted in boldface (p < 0.050, one-tailed p-value). *CI does not include/cross zero.