Table 3.

Pairwise comparisons in sleep variables between caffeine patterns.

Group	Comparison Group	TST (Hours)	SE (%)	SOL (Minutes)	REM (Hours)
No Caffeine	Morning Caffeine	−0.03	1.16	−0.22	−0.02
No Caffeine	Afternoon Caffeine	0.00	−1.88	16.96*	−0.15
No Caffeine	Evening Caffeine	−0.42	−5.37**	18.30*	−0.24
No Caffeine	Heavy Evening Caffeine	−1.43**	−13.41***	54.86***	−0.57*
Morning Caffeine	Afternoon Caffeine	0.03	−3.04	17.18	−0.13
Morning Caffeine	Evening Caffeine	−0.40	−6.53	18.52	−0.21
Morning Caffeine	Heavy Evening Caffeine	−1.40*	−14.57***	55.08**	−0.54
Afternoon Caffeine	Evening Caffeine	−0.42	−3.49	1.34	−0.08
Afternoon Caffeine	Heavy Evening Caffeine	−1.43**	−11.53***	37.90*	−0.41
Evening Caffeine	Heavy Evening Caffeine	−1.01	−8.03	36.56*	−0.33

Values reflect mean differences between groups. Significance is denoted as follows: *P < .05, **P < .01, ***P < .001. REM = rapid eye movement, SE = sleep efficiency, SOL = sleep-onset latency, TST= total sleep time.