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. 2021 Aug 25;45(2):zsab216. doi: 10.1093/sleep/zsab216

Table 4.

Change in sleep shown as percentage (%) of those reporting decrease, no change, or increase

Definitive evening-types Moderate evening-types Intermediate-types Moderate morning-types Definitive morning-types Pa
Sleep per night in hours <0.001
 Decreased 31.2 28.3 22.8 26.6 27.9
 Unchanged 23.4 31.4 47.8 40.8 46.7
 Increased 45.4 40.3 29.4 32.6 25.5
Sleep per 24 h in hours <0.001
 Decreased 25.3 25.4 24.8 27.5 28.7
 Unchanged 25.3 31.2 44.7 38.7 43.7
 Increased 49.3 43.4 30.6 33.8 27.5
Bedtime on working days <0.001
 Earlier 9.5 9.8 8.5 7.4 10.4
 Unchanged 24.2 38.6 58.0 48.7 53.1
 Later 66.3 51.6 33.4 43.9 36.5
Wake-up time at working days <0.001
 Earlier 14.6 13.6 15.4 17.1 19.9
 Unchanged 19.2 25.2 39.3 31.7 40.2
 Later 66.2 61.1 45.3 51.2 39.9
Bedtime on free days <0.001
 Earlier 9.7 10.9 11.1 11.1 12.3
 Unchanged 33.4 40.0 56.4 48.3 50.9
 Later 56.8 49.1 32.5 40.6 36.8
Wake-up time on free days <0.001
 Earlier 20.5 21.5 19.4 22.5 22.9
 Unchanged 30.7 38.3 52.7 45.2 49.1
 Later 48.8 40.2 28.0 32.3 28.0
Midpoint of sleep at working days <0.001
 Earlier 11.5 12.3 12.1 11.5 12.8
 Unchanged 15.2 26.2 40.3 32.5 42.3
 Later 73.3 61.5 47.6 56.0 44.9
Midpoint of sleep at free days <0.001
 Earlier 18.8 21.8 16.3 20.2 20.5
 Unchanged 21.2 30.2 46.4 36.6 36.1
 Later 60.0 48.0 37.3 43.2 43.4
Poor sleep quality <0.001
 Decreased 15.8 16.2 11.7 13.4 10.9
 Unchanged 36.5 41.9 58.6 46.7 50.5
 Increased 47.7 42.0 29.7 39.9 38.6
Sleep onset problems <0.001
 Decreased 11.9 12.8 9.4 10.4 9.0
 Unchanged 43.0 45.1 62.2 53.6 58.3
 Increased 45.2 42.1 28.4 36.0 32.7
Sleep maintenance problems <0.001
 Decreased 10.2 9.6 8.8 9.8 9.1
 Unchanged 53.1 57.3 66.3 56.9 58.7
 Increased 36.7 33.1 24.9 33.3 32.2
Early morning awakening <0.001
 Decreased 13.9 11.9 8.7 10.3 10.7
 Unchanged 55.0 57.1 69.0 59.5 59.9
 Increased 31.1 30.9 22.3 30.2 29.4
Hypnotics use <0.001
 Decreased 3.9 1.7 2.2 1.8 2.0
 Unchanged 86.5 92.1 92.3 92.2 90.6
 Increased 9.6 6.2 5.5 6.0 7.4
Excessive sleepiness <0.001
 Decreased 19.9 19.0 13.7 16.8 12.3
 Unchanged 43.9 48.7 63.7 53.1 58.6
 Increased 36.3 32.3 22.6 30.1 29.1
Fatigue <0.001
 Decreased 21.3 19.8 15.8 19.2 13.6
 Unchanged 39.6 46.3 59.8 50.3 55.2
 Increased 39.1 33.9 24.3 30.5 31.2
Nightmares <0.001
 Decreased 7.0 5.8 5.3 6.3 5.2
 Unchanged 54.3 62.5 73.1 66.7 68.9
 Increased 38.7 31.8 21.6 27.0 25.9

a Difference between circadian types were analyzed with chi-square tests.