TABLE 4.

Results from the reaction time test administered at 22:00 in the evening and at 10:00 on the following morning in the participants with delayed sleep–wake phase disorder (DSWPD) and controls.

	Controls1 (n = 20)	DSWPD1 (n = 39)	Effect size	T-test	ANOVA (p-value)
					(group × weekday/weekend)
	Mean ± SD	Mean ± SD	Cohen’s d	p	Time	Group	Interaction
Mean reaction time (ms)2
Evening	295.2 ± 46.9	296.5 ± 63.7	0.02	0.975	0.151	0.061	0.001
Morning	258.9 ± 34.3	312.0 ± 65.7	1.01	0.024
Median reaction time (ms)3
Evening	278.8 ± 43.7	279.0 ± 57.3	0.00	0.967	0.065	0.099	0.001
Morning	245.3 ± 30.1	288.6 ± 59.9	0.91	0.042
Lapses (#)4
Evening	2.3 ± 2.3	3.4 ± 6.1	0.24	0.481	0.579	0.044	0.013
Morning	1.0 ± 1.3∗	5.4 ± 6.9∗	0.89	<0.001

The table shows mean ± standard deviation (SD), Cohen’s d as a measure of effect size, results from group × time ANOVAs, and results from pairwise independent t-tests for simple effects. ¹Two extreme outliers were identified and omitted from the analyses, leaving n = 20 in the control group and n = 39 in the DSWPD group. ²Mean reaction time = mean of all responses between 120 and 1750 ms. ³Median reaction time = median of all responses between 120 and 1750 ms. ⁴Lapses = the number of responses between 500 and 1750 ms. ^∗p < 0.05 paired samples t-test within each group.