Skip to main content

Table 1 Characteristics of study participants by sex (Japan, 2001–2008)

From: Lifestyle factors associated with underweight among Japanese adolescents: a cross-sectional study

 

Boys (N = 1211)

Girls (N = 1139)

P valuea

Age (years)

12.0 (12.0, 13.0)

12.0 (12.0, 13.0)

0.822

Bitrhweight (g), n (%)

  < 2500

77 (6.4)

85 (7.5)

0.291

  ≥ 2500

1134 (93.6)

1054 (92.5)

 

Height (cm)

155.6 (149.2, 161.0)

153.3 (149.4, 157.2)

<0.001

Weight (kg)

44.3 (38.8, 50.8)

43.5 (38.9, 48.1)

0.007

BMI (kg/m2)

18.2 (16.8, 20.0)

18.3 (16.9, 20.0)

0.389

BMI-SDS

0.25(−0.35, 0.89)

0.15 (−0.44, 0.75)

0.002

Physique, n (%)

 Underweight

99 (8.2)

127 (11.2)

0.005

 Normal weight

933 (77.0)

882 (77.4)

 

 Overweight/obesity

179 (14.8)

130 (11.4)

 

Exercise, n (%)

 Daily

1003 (82.8)

668 (58.7)

<0.001

 Sometimes

94 (7.8)

157 (13.8)

 

 None

114 (9.4)

314 (27.6)

 

Skipping breakfast, n (%)

 Yes

58 (4.8)

84 (7.4)

0.009

 No

1153 (95.2)

1055 (92.6)

 

Snacking after dinner, n (%)

 Always or often

735 (60.7)

659 (57.9)

0.162

 Seldom or none

476 (39.3)

480 (42.1)

0.015

Snacking while watching television or reading books, n (%)

 Yes

482 (39.8)

510 (44.8)

0.015

 No

729 (60.2)

629 (55.2)

 

Eating slowly, n (%)

 Yes

207 (17.1)

279 (24.5)

<0.001

 No

1004 (82.9)

860 (75.5)

 
  1. BMI body mass index, BMI-SDS body mass index standard deviation score
  2. Except where indicated n (%), values are expressed as median (25, 75th percentile)
  3. aWilcoxon rank-sum test or chi-square test