Table 1

Basic information, sociodemographic characteristics and lifestyle characteristics

VariablesNormal-sleep quality group
(n=160)
Low-sleep quality group (n=138)χ2 P valueEffect size95% CI
LowerUpper
Age (years)20.8±1.420.7±1.30.666−0.0250.0000.000
Age at menarche (years)12.5±1.712.5±1.50.8390.0120.0000.000
Body mass index (kg/m2)20.5±2.620.8±2.60.8840.008−0.5210.459
Part-time job
 Yes135 (84.4)123 (89.1)1.4420.2300.0700.0040.168
 No25 (15.6)15 (10.9)
Living status
 Alone57 (35.6)46 (33.3)0.1720.6780.0240.0020.143
 With others103 (64.4)92 (66.7)
Alcohol intake
 Low145 (90.6)129 (93.5)0.8150.3670.0520.0030.169
 High15 (9.4)9 (6.5)
Smoking
 No152 (95.0)133 (96.4)0.3370.5620.0340.0020.149
 Yes8 (5.0)5 (0.6)
Breakfast
 Eating114 (71.3)81 (58.7)5.1630.023*0.1320.0160.245
 Not eating46 (28.7)57 (41.3)
Eating between meals
 Eating101 (63.1)95 (68.8)1.0750.3000.0600.0040.172
 Not eating59 (36.9)43 (31.2)
Caffeine consumption (≥3 times/week)
 Yes74 (46.3)57 (41.3)0.7360.3910.0500.0310.234
 No86 (53.7)81 (58.7)
Studying until going to bed (≥3 times/week)
 Yes37 (23.1)32 (23.2)0.0000.9900.0010.0160.183
 No123 (76.9)106 (76.8)
Watching TV until going to bed (≥3 times/week)
 Yes44 (27.5)29 (21.0)1.6850.1940.0750.0230.206
 No116 (72.5)109 (79.0)
Screen time
 Leisure (min/day)256.4±204.2252.1±144.00.5780.032−30.00030.000
 Study (min/day)105.9±129.8107.1±124.40.2650.064−20.0000.000
  • Data are expressed as mean±SD, or n (%).

  • *Statistically significant.