Table 3 The logistic regression analysis and the trend test

<6.5%

82

9

1.000(Reference)

1.000(Reference)

1.000(Reference)

6.5 to 8%

236

28

1.450 (0.607–3.464)

1.453 (0.606–3.482)

1.248 (0.512–3.044)

8 to 9.5%

197

30

2.005 (0.844–4.759)

2.015 (0.846–4.800)

1.553 (0.643–3.804)

9.5 to11%

99

25

3.642 (1.483–8.945)

3.602 (1.459–8.894)

2.625 (1.025–6.718)

>11%

27

13

9.753 (3.268–29.114)

9.791 (3.260–29.409)

5.829 (1.785–19.034)

P for trend

–

–

<0.0001

<0.0001

<0.0001