Table 1 The basic characteristics of the study population
CRL(cm) | Number | Age(years) | CM(mm) | IT(mm) | BS(mm) | BSOB(mm) | BS/BSOB |
|---|---|---|---|---|---|---|---|
4.5 ~ 5.4 | 80 | 31.0 (28.0,34.0) | 1.1 (1.0,1.2) | 1.7 (1.5,1.8) | 2.2 (2.0,2.4) | 3.5 (3.3,3.7) | 0.61 (0.57,0.69) |
5.5 ~ 6.4 | 749 | 31.0 (29.0,33.0) | 1.4 (1.3,1.6) | 1.8 (1.7,1.9) | 2.5 (2.4,2.7) | 4.0 (3.8,4.3) | 0.62 (0.57,0.68) |
6.5 ~ 7.4 | 728 | 31.5 (29.0,34.0) | 2.0 (1.8,2.1) | 1.9 (1.8,2.0) | 2.8 (2.6,2.9) | 4.6 (4.4,4.9) | 0.60 (0.57,0.64) |
7.5 ~ 8.4 | 106 | 32.0 (29.0,35.0) | 2.4 (2.1,2.6) | 2.1 (2.0,2.3) | 3.1 (2.9,3.2) | 5.3 (5.0,5.6) | 0.58 (0.55,0.62) |