Table 4.

Coefficients/estimates, standard errors (in brackets), and confidence intervals for the fixed effects of interest and random effects for the Executive Functioning Index models.^a

Parameter		DAUb only, estimate (SE), 95% CI	P value	ACEsc and DAU, estimate (SE), 95% CI	P value
Fixed effects
	Intercept	94.77 (0.91), 92.98 to 96.56	<.001	97.92 (1.37), 95.23 to 100.61	<.001
	DAU	0.03 (0.04), −0.02 to 0.10	.43	0.00 (0.06), −0.10 to 0.11	.95
	ACEs	N/Ad	N/A	−1.24 (0.41), −2.04 to −0.43	.003
	ACEs × DAU	N/A	N/A	0.01 (0.02), −0.02 to 0.04	.55
Variance components
	Residual	30.88 (3.56), 24.63 to 38.72	N/A	30.72 (3.53), 24.52 to 38.48	N/A
	Intercept	102.97 (13.55), 79.56 to 133.26	N/A	96.56 (12.83), 74.43 to 125.28	N/A
	Slope	0.04 (0.02), 0.02 to 0.12	N/A	0.05 (0.02), 0.02 to 0.12	N/A

^aThe number of observations in these models at level 1 (timepoint) is 416; at level 2 (participant) it is 155.

^bDAU: days of app usage.

^cACEs: adverse childhood experiences.

^dN/A: not applicable.