Table 1.
Description of the sample; unadjusted and adjusted odds ratios for the effect of each risk factor on late antenatal booking
|
Risk factor |
n |
% |
Unadjusted analysis |
Adjusted analysis * |
|||
|---|---|---|---|---|---|---|---|
| |
|
|
|
n = 20,135 |
n = 19,316 |
||
| OR | [95% CI] | OR | [95% CI] | ||||
| Self-Defined Ethnicity |
British (White) |
3,875 |
19.25 |
1.00 |
|
1.00 |
|
| |
African (except Somali) |
2,715 |
13.48 |
2.03 |
[1.83, 2.25] |
1.56 |
[1.38, 1.77] |
| Somali |
480 |
2.38 |
3.11 |
[2.56, 3.77] |
1.58 |
[1.28, 1.96] |
|
| Caribbean |
591 |
2.94 |
1.44 |
[1.20, 1.73] |
1.33 |
[1.09, 1.61] |
|
| Eastern European |
2,531 |
12.57 |
1.90 |
[1.71, 2.11] |
1.49 |
[1.32, 1.69] |
|
| Other White |
395 |
1.96 |
1.34 |
[1.08, 1.67] |
1.04 |
[0.82, 1.32] |
|
| Bangladeshi (inc British) |
2,867 |
14.24 |
1.55 |
[1.40, 1.72] |
1.20 |
[1.07, 1.34] |
|
| Indian (inc British) |
1,842 |
9.15 |
1.34 |
[1.19, 1.51] |
1.11 |
[0.97, 1.26] |
|
| Pakistani (inc. British) |
3,109 |
15.44 |
1.35 |
[1.22, 1.50] |
1.16 |
[1.04, 1.29] |
|
| Other Asian |
957 |
4.75 |
1.58 |
[1.37, 1.83] |
1.16 |
[0.97, 1.40] |
|
| Other |
685 |
3.4 |
1.64 |
[1.38, 1.94] |
1.16 |
[0.98, 1.36] |
|
| Missing values |
88 |
0.44 |
|
|
|
|
|
| Age at booking (years) |
<20 |
980 |
4.87 |
1.37 |
[1.20, 1.58] |
1.32 |
[1.13, 1.54] |
| |
20-24 |
4,578 |
22.74 |
1.00 |
|
1.00 |
|
| 25-29 |
7,137 |
35.45 |
0.73 |
[0.67, 0.79] |
0.75 |
[0.69, 0.82] |
|
| 30-34 |
4,811 |
23.89 |
0.71 |
[0.65, 0.77] |
0.72 |
[0.65, 0.79] |
|
| 35-39 |
2,070 |
10.28 |
0.75 |
[0.68, 0.84] |
0.68 |
[0.60, 0.78] |
|
| ≥40 |
551 |
2.74 |
0.83 |
[0.69, 0.99] |
0.71 |
[0.58, 0.88] |
|
| Missing values |
8 |
0.04 |
|
|
|
|
|
| Parity |
No previous live births |
9,815 |
48.75 |
1.10 |
[1.02, 1.18] |
0.99 |
[0.92, 1.07] |
| 1 previous live birth |
5,517 |
27.4 |
1.00 |
|
1.00 |
|
|
| 2 previous live births |
2,763 |
13.72 |
1.14 |
[1.04, 1.25] |
1.17 |
[1.06, 1.30] |
|
| 3 previous live births |
1,167 |
5.8 |
1.34 |
[1.18, 1.52] |
1.43 |
[1.24, 1.64] |
|
| 4+ previous live births |
854 |
4.24 |
2.06 |
[1.78, 2.39] |
2.09 |
[1.77, 2.46] |
|
| Missing values |
19 |
0.09 |
|
|
|
|
|
| Woman’s occupation |
Managerial/professional |
2,444 |
12.14 |
1.00 |
|
1.00 |
|
| |
Lower supervisory/technical |
2,492 |
12 |
1.12 |
[0.99, 1.27] |
1.01 |
[0.88, 1.15] |
| Semi-routine & routine |
3,319 |
16.48 |
1.59 |
[1.42, 1.79] |
1.15 |
[1.02, 1.31] |
|
| Self-employed |
177 |
0.88 |
2.22 |
[1.63, 3.02] |
1.52 |
[1.09, 2.11] |
|
| Housewife |
6,968 |
34.61 |
1.85 |
[1.67, 2.05] |
1.25 |
[1.11, 1.41] |
|
| Unclassifiable |
4,735 |
23.52 |
2.34 |
[2.10, 2.60] |
1.59 |
[1.42, 1.80] |
|
| Missing values |
0 |
0 |
|
|
|
|
|
| Language ability |
English speaker |
13,466 |
66.88 |
1.00 |
|
1.00 |
|
| Non-English speaker |
6,539 |
32.48 |
1.51 |
[1.42, 1.60] |
1.39 |
[1.29, 1.50] |
|
| Missing values |
130 |
0.65 |
|
|
|
|
|
| Birthplace |
Born in the UK |
4,464 |
22.17 |
1.00 |
|
1.00 |
|
| Born outside the UK |
15,666 |
77.8 |
1.52 |
[1.41, 1.63] |
1.33 |
[1.21, 1.46] |
|
| Missing values |
5 |
0.02 |
|
|
|
|
|
| Housing status |
Owner-occupier |
3,752 |
18.63 |
1.00 |
|
1.00 |
|
| Rented |
14,060 |
69.83 |
1.65 |
[1.52, 1.78] |
1.36 |
[1.25, 1.48] |
|
| Temporary accommodation |
344 |
1.71 |
2.54 |
[2.03, 3.18] |
1.71 |
[1.35, 2.16] |
|
| Other |
1,281 |
6.36 |
2.51 |
[2.20, 2.86] |
1.94 |
[1.68, 2.22] |
|
| Missing values |
698 |
3.47 |
|
|
|
|
|
| Year of Booking |
2008 |
6,476 |
32.16 |
1.00 |
|
1.00 |
|
| 2009 |
6,450 |
32.03 |
0.60 |
[0.56, 0.65] |
0.62 |
[0.57, 0.66] |
|
| 2010 |
6,775 |
33.65 |
0.45 |
[0.42, 0.49] |
0.48 |
[0.44, 0.52] |
|
| 2011 |
434 |
2.16 |
0.50 |
[0.41, 0.62] |
0.53 |
[0.44, 0.66] |
|
| Missing values | 0 | 0 | |||||
OR, Odds ratio; CI, Confidence interval.
* Each variable adjusted for all other variables in the model.