Effects of an irregular bedtime schedule on sleep quality, daytime sleepiness, and fatigue among university students in Taiwan

Table 2 Number (%) of subjects in each irregular bedtime frequency group with an average daily sleep time <7 h/day, 7–8 h/day, or >8 h/day

ADST*	Irregular bedtime frequency⁺			Total
	Low	Intermediate	High
<7 h/day	14 (8.8)	26 (16.3)	35 (21.9)	75 (46.9)
7–8 h/day	17 (10.6)	24 (15.0)	10 (6.3)	51 (31.9)
>8 h/day	12 (7.5)	12 (7.5)	10 (6.3)	34 (21.3)
Total	43 (26.9)	62 (38.8)	55 (34.4)	160 (100)

ADST, average daily sleep time
⁺ An irregular bedtime event was defined as a shift from the usual bedtime of >1 h. This occurred <1 night/week for the low-frequency group, 1–3 nights/week for the intermediate-frequency group, and >3 nights/week for the high-frequency group.
*Chi-Square analysis indicated that average daily sleep time differed significantly across the irregular bedtime frequency groups (χ² = 11.68, p = 0.022); as supported by a significant Spearman correlation (r = -0.22, p = 0.05).

ISSN: 1471-2458