Table 1 Biographical variables, life habits, and number of night and evening shifts/month among the JFCT members
DW (n = 8) | ONEW (n = 14) | Night shift worker | One-factor ANOVA or Fisher’s exact test | |||
|---|---|---|---|---|---|---|
SWSD− (n = 16) | SWSD+ (n = 14) | F value | p value | |||
Number of subjects who had symptoms of insomnia or excessive wake time sleepiness | 0 | 7 (50 %) | 0 | 14 (100 %) | ||
Age (years) | 37.5 ± 7.6 | 39.8 ± 5.5 | 37.8 ± 5.8 | 38.1 ± 6.8 | 0.346 | 0.792 |
Number of female subjects | 3 | 2 | 1 | 0 | 0.043 | |
BMI | 21.2 ± 2.2 | 22.1 ± 2.3 | 22.0 ± 1.6 | 21.8 ± 3.2 | 0.26 | 0.854 |
Length of experience as a flight controller (years) | 2.2 ± 2.0 | 4.3 ± 0.9 | 3.8 ± 1.3 | 3.8 ± 1.2 | 1.886 | 0.145 |
One-way commuting time (min) | 18 ± 12 | 23 ± 9 | 25 ± 18 | 28 ± 32 | 0.442 | 0.724 |
Number of subjects living alone | 3 (38 %) | 0 | 3 (19 %) | 4 (29 %) | 0.077 | |
Number of subjects living with an infant | 4 (50 %) | 9 (64 %) | 4 (25 %) | 5 (36 %) | 0.162 | |
Diurnal score | 16.0 ± 5.1 | 15.8 ± 2.9 | 16.3 ± 3.3 | 15.6 ± 2.3 | 0.098 | 0.961 |
Habitual exerciser | 1 (13 %) | 5 (36 %) | 6 (40 %) | 4 (29 %) | 0.682 | |
Habitual drinker | 1 (13 %) | 3 (21 %) | 2 (13 %) | 2 (14 %) | 0.951 | |
Smoker | 0 | 0 | 1 (7 %) | 2 (14 %) | 0.473 | |
Heavy caffeine drinker | 1 (13 %) | 2 (14 %) | 4 (25 %) | 1 (7 %) | 0.716 | |
Days of night shift/month | 0 | 1.4 ± 0.9 | 4.9 ± 1.3 | 4.3 ± 1.4 | 49.44 | <0.0001 |
Days of evening shift/month | 0 | 4.0 ± 3.8 | 3.4 ± 1.5 | 3.6 ± 1.6 | 5.833 | 0.002 |