Table 2

Rates and crude odds ratio for factors associated with non-registration, New South Wales, Australia, 2001–2005 (n = 427,073)
Registered Non-registered
n n1 % n2 % Crude ORa 95% CI
Indigenous status* Indigenous 14,055 10,023 71.31 4,032 28.69 4.96 4.77 5.16
Non- indigenous 413,009 382,031 92.50 30,978 7.50 1
Missing 9 2 22.22 7 77.78
Total 427,073 392,056 91.80 35,017 8.20
Maternal age* 25–39 332,866 310,270 93.21 22,596 6.79 1
<25 or >39 94,193 81,786 86.83 12,407 13.17 2.08 2.04 2.13
Total 427,059 392,056 91.80 35,003 8.20
Birthweight (grams)* ≥2500g 401,750 370,078 92.12 31,672 7.88 1
<2500g 25,310 21,973 86.82 3,337 13.18 1.78 1.71 1.84
Missing 13 5 38.46 8 61.54
Total 427,073 392,056 91.80 35,017 8.20
Plurality Singleton 413,464 379,569 91.80 33,895 8.20 1
Multiple 13,609 12,487 91.76 1,122 8.24 1.01 0.95 1.07
Total 427,073 392,056 91.80 35,017 8.20
Quarters*b First 105,448 99,499 94.36 5,949 5.64 1
Second 105,777 99,522 94.09 6,255 5.91 1.05 1.01 1.09
Third 109,978 102,812 93.48 7,166 6.52 1.17 1.13 1.21
Fourth 83,746 78,118 93.28 5,628 6.72 1.20 1.16 1.25
Total 404,949 379,951 93.83 24,998 6.17
Number of previous pregnancies* 0 178,720 168,657 94.37 10,063 5.63 1
1 143,915 132,948 92.38 10,967 7.62 1.38 1.34 1.42
2 65,243 58,267 89.31 6,976 10.69 2.01 1.94 2.07
3 23,702 20,087 84.75 3,615 15.25 3.02 2.90 3.14
4+ 15,215 11,841 77.82 3,374 22.18 4.78 4.57 4.99
Missing 278 256 92.09 22 7.91
Total 427,073 392,056 91.80 35,017 8.20
Remoteness* Major cities 321,503 299,357 93.11 22,146 6.89 1
Other areas 105,570 92,699 87.81 12,871 12.19 1.88 1.83 1.92
Total 427,073 392,056 91.80 35,017 8.20
Mother’s country of birth* Australia 301,335 278,314 92.36 23,021 7.64 1
Other countries 119,776 113,700 94.93 6,076 5.07 0.65 0.63 0.67
Missingc 5,962 42 0.70 5,920 99.30
Total 427,073 392,056 91.80 35,017 8.20
Neonatal or postneonatal death No 425,870 391,172 91.85 34,698 8.15 1
Yes 1,203 884 73.48 319 26.52 4.07 3.58 4.62
Total 427,073 392,056 91.80 35,017 8.20
Year of birth 2001 84,470 79,796 94.47 4,674 5.53 1
2002 84,609 80,141 94.72 4,468 5.28 0.95 0.91 0.99
2003 85,000 79,949 94.06 5,051 5.94 1.08 1.03 1.12
2004 84,095 78733 93.62 5,362 6.38 1.16 1.12 1.21
2005 88,899 73,437 82.61 15,462 17.39 3.59 3.47 3.72
Total 427,073 392,056 91.80 35,017 8.20

a Crude odds ratio (OR).

* Crude odds ratio is significantly different.

b The data from October to December 2005 were excluded because of the interval between birth and registration.

c The missing records of mother’s country of birth were mainly missing from the MDC in 2001 and 2002.

Xu et al.

Xu et al. BMC Pregnancy and Childbirth 2012 12:147   doi:10.1186/1471-2393-12-147

Open Data