Table 3 Contribution of Robson ten obstetric groups to the overall caesarean section rate
Robson Group | Number of women (n1) | Relative size of Robson group (%) n1/N1 | Number of CS (n2) | Group specific CS (%) n2/n1 | Group input to total CS (%) n2/N2 | Group input to overall CS rate (%) n2/N1 |
|---|---|---|---|---|---|---|
1 | 86 | 19.2 | 21 | 24.4 | 9.2 | 4.7 |
2 2a 2b | 38 19 19 | 8.5 4.3 4.3 | 32 13 19 | 84.2 68.4 100.0 | 14.0 5.7 8.3 | 7.2 2.9 4.3 |
3 | 136 | 30.4 | 23 | 16.9 | 10.0 | 5.1 |
4 4a 4b | 18 7 11 | 4.0 1.6 2.5 | 15 4 11 | 83.3 57.1 100.0 | 6.6 1.8 4.8 | 3.3 0.9 2.4 |
5 5.1 5.2 | 81 66 15 | 18.1 14.8 3.4 | 79 64 15 | 97.5 97.0 100.0 | 34.5 27.9 6.6 | 17.7 14.3 3.3 |
6 | 5 | 1.1 | 5 | 100.0 | 2.2 | 1.1 |
7 | 9 | 2.0 | 8 | 88.9 | 3.5 | 1.8 |
8 | 20 | 4.5 | 11 | 55.0 | 4.8 | 2.5 |
9 | 6 | 1.3 | 6 | 100.0 | 2.6 | 1.3 |
10 | 49 | 11.0 | 29 | 59.2 | 12.6 | 6.5 |
Total | 447 | 100.0 | 229 | NA | 100.0 | 51.2 |