| |
Chi-square test
|
Birthweight
| | | |
Normal/high birthweight (≥2500 g)
|
94.2 (9784)
|
93.9 (7775)
|
95.3 (2009)
|
Low birthweight (<2500 g)
|
5.8 (596)
|
6.1 (499)
|
4.7 (97)
|
| |
p < 0.05
|
Pre-term birth
| | | |
Normal (≥37 weeks)
|
93.1 (9708)
|
93.2 (7738)
|
93.0 (1970)
|
Pre-term (<37 weeks)
|
6.9 (695)
|
6.8 (552)
|
7.1 (143)
|
| |
p = 0.77
|
Maternal age at child’s birth
| | | |
14–19 years
|
7.2 (647)
|
7.2 (515)
|
7.1 (132)
|
20–29 years
|
44.6 (4575)
|
44.7 (3634)
|
44.5 (941)
|
30–39 years
|
45.9 (4994)
|
46.0 (3996)
|
45.7 (998)
|
40+ years
|
2.2 (258)
|
2.1 (200)
|
2.8 (58)
|
| |
p = 0.49
|
Maternal ethnicity
| | | |
White
|
88.0 (9057)
|
88.4 (7234)
|
86.3 (1823)
|
Non-white
|
12.0 (1393)
|
11.6 (1091)
|
13.7 (302)
|
| |
p < 0.05
|
Maternal pre-pregnancy bodysize
| | | |
Normal / underweight
|
71.0 (6964)
|
75.0 (5871)
|
54.7 (1093)
|
Overweight
|
29.0 (2988)
|
25.0 (2071)
|
45.3 (917)
|
| |
p < 0.001
|
Family structure (9-months–7-years)
| | | |
Continuous couple families
|
72.1 (7728)
|
73.1 (6227)
|
67.9 (1501)
|
Couple families for 1–3 sweeps
|
20.9 (2042)
|
20.2 (1594)
|
23.4 (448)
|
Continuous lone-parent families
|
7.1 (704)
|
6.7 (524)
|
8.8 (180)
|
| |
p < 0.001
|
Maternal highest qualification (9-months)a
| | | |
Degree
|
17.9 (2028)
|
19.1 (1729)
|
12.8 (299)
|
Diploma
|
9.4 (1026)
|
9.5 (820)
|
9.1 (206)
|
A/AS/S Levels
|
9.8 (1088)
|
10.1 (887)
|
8.8 (201)
|
O Levels/GCSEs A-C
|
35.7 (3592)
|
35.2 (2797)
|
37.7 (795)
|
O Levels/GCSEs D-G
|
10.9 (1057)
|
10.5 (817)
|
12.6 (240)
|
Other academic qualification
|
2.0 (218)
|
1.8 (171)
|
2.5 (47)
|
None of these qualifications
|
14.3 (1456)
|
13.8 (1117)
|
16.6 (339)
|
| |
p < 0.001
|
Breastfeeding duration
| | | |
Never
|
31.2 (3161)
|
30.4 (2434)
|
34.6 (727)
|
Up to 4 months
|
40.8 (4407)
|
40.7 (3515)
|
41.0 (892)
|
Greater than 4 months
|
28.0 (2906)
|
28.9 (2396)
|
24.4 (510)
|
| |
p < 0.001
|
Introduced to solids before 4-months of age
| | | |
No
|
64.0 (6753)
|
64.9 (5462)
|
60.4 (1291)
|
Yes
|
36.0 (3719)
|
35.1 (2881)
|
39.6 (838)
|
| |
p < 0.001
|
Maternal smoking during pregnancy
| | | |
No
|
65.6 (7006)
|
66.6 (5676)
|
61.7 (1330)
|
Yes
|
34.4 (3439)
|
33.4 (2645)
|
38.3 (794)
|
| |
p < 0.001
|
Number of children in household at first sweep (9-months)
| | | |
1
|
42.0 (4365)
|
42.3 (3484)
|
40.8 (881)
|
2
|
36.6 (3755)
|
36.7 (2994)
|
36.3 (761)
|
3
|
14.5 (1592)
|
14.4 (1275)
|
15.2 (317)
|
4+
|
6.9 (762)
|
6.7 (592)
|
7.7 (170)
|
| |
p = 0.29
|