Table 4 CFR in 12-year-old Chinese children by gender (%, 95%CI)

17.4 (16.5–18.3)

17.1 (15.8–18.5)

17.6 (16.4–18.8)

0.641

23.8 (22.5–25.0)

23.8 (21.8–25.8)

23.8 (22.1–25.4)

0.983

6.4 (5.5–7.4)

6.5 (5.1–8.0)

6.3 (5.0–7.7)

0.848

23.4 (22.0–24.8)

23.5 (21.3–25.7)

23.4 (21.6–25.2)

0.920

10.4 (8.9–11.9)

10.8 (8.5–13.2)

10.1 (8.1–12.1)

0.651

10.6 (9.0–12.1)

10.3 (8.1–12.5)

10.8 (8.6–12.9)

0.758

22.8 (21.7–24.0)

22.1 (20.3–23.9)

23.3 (21.8–24.9)

0.333

33.3 (31.5–35.1)

32.1 (29.4–34.8)

34.2 (31.8–36.6)

0.247

9.7 (8.5–11.0)

8.4 (6.6–10.3)

10.5 (8.9–12.2)

0.107

26.0 (24.5–27.6)

25.4 (23.0–27.8)

26.5 (24.5–28.5)

0.507

17.8 (14.9–20.8)

18.4 (14.0–22.8)

17.4 (13.4–21.3)

0.736

16.8 (14.6–18.9)

15.7 (12.4–19.0)

17.5 (14.6–20.4)

0.410

19.3 (18.3–20.4)

20.2 (18.5–21.8)

18.7 (17.4–20.1)

0.176

25.6 (24.0–27.2)

25.8 (23.3–28.3)

25.4 (23.4–27.5)

0.796

12.4 (11.2–13.7)

14.2 (12.1–16.3)

11.2 (9.6–12.7)

0.020

26.8 (25.1–28.5)

28.5 (25.8–31.2)

25.7 (23.5–27.8)

0.103

11.9 (10.0–13.8)

10.4 (7.7–13.1)

13.0 (10.4–15.6)

0.179

12.5 (10.9–14.1)

14.2 (11.7–16.8)

11.2 (9.3–13.2)

0.064

23.4 (22.6–24.2)

23.8 (22.6–24.9)

23.1 (22.1–24.1)

0.677

27.8 (26.8–28.9)

28.5 (26.9–30.1)

27.3 (26.0–28.7)

0.278

16.3 (15.2–17.3)

16.1 (14.4–17.7)

16.4 (15.0–17.8)

0.767

26.9 (25.2–28.5)

28.9 (26.2–31.6)

25.6 (23.5–27.7)

0.060

10.6 (9.2–12.0)

10.0 (7.9–12.1)

11.0 (9.1–12.9)

0.494

25.4 (24.4–26.4)

25.5 (24.0–27.0)

25.3 (23.9–26.6)

0.854

15.6 (14.9–16.3)

14.9 (13.8–16.1)

16.0 (15.1–16.9)

0.161

18.7 (17.6–19.8)

18.7 (16.9–20.5)

18.7 (17.3–20.1)

0.998

12.5 (11.5–13.4)

11.3 (9.9–12.7)

13.2 (12.0–14.5)

0.043

23.1 (21.8–24.3)

22.4 (20.4–24.3)

23.5 (21.9–25.1)

0.377

11.2 (9.8–12.5)

12.3 (10.1–14.6)

10.4 (8.8–12.1)

0.172

7.3 (6.3–8.2)

5.5 (4.1–6.8)

8.5 (7.2–9.8)

0.002