Table 3 Results of subgroup analysis stratified by independent variables

Male

 Grade

  7—9

1.00

1.53

(1.37–1.72)

1.77

(1.50–2.09)

1.34

(1.24–1.44)

  10—12

1.00

1.21

(1.07–1.37)

1.14

(0.96–1.35)

1.26

(1.17–1.36)

 Living type

  With parents

1.00

1.39

(1.27–1.51)

1.44

(1.27–1.62)

1.30

(1.22–1.37)

  Others

1.00

1.11

(0.80–1.53

1.13

(0.68–1.89)

1.39

(1.12–1.72)

Female

 Grade

  7—9

1.00

1.55

(1.41–1.71)

1.55

(1.32–1.82)

1.32

(1.23–1.41)

  10—12

1.00

1.36

(1.21–1.52)

1.46

(1.24–1.74)

1.18

(1.09–1.28)

 Living type

  With parents

1.00

1.46

(1.36–1.58)

1.51

(1.34–1.70)

1.25

(1.19–1.32)

  Others

1.00

1.41

(0.99–2.00)

1.68

(0.86–3.30)

1.05

(0.77–1.44)