Table 2.

Comparison of low and high caffeine exposure groups using a generalized estimating equation model

Parameter	Estimate	Error	95% CI	Z	Pr > |Z|
Intercept	1.16	1.56	−1.89, 4.21	0.74	0.46
Caffeine
Group
Low	0.72	0.26	0.21, 1.23	2.77	0.006
High	0	0	0, 0	.	.
GA	−0.04	0.05	−0.14, 0.07	−0.70	0.48
PNA	0.01	0.00	0.00, 0.02	1.36	0.17
Location
Left Frontal	0.21	0.19	−0.16, 0.58	1.13	0.26
Right Frontal	0.04	0.17	−0.29, 0.38	0.26	0.80
Left Temporal	0.28	0.18	−0.07, 0.64	1.56	0.12
Right Temporal	0	0	0, 0	.	.

Pr >Z: probability