Risk of unexplained death in infancy, by ethnic group and other factors. Live singleton births at 22+weeks, England and Wales 2006–2012
| Factor | Births | Unexplained infant deaths | Rate (95% CI) | OR (95% CI) | ||
| N | % | n | % | Crude per 1000 | Adjusted for birth year | |
| Ethnic group | ||||||
| White British (ref) | 3 009 144 | 65 | 1129 | 72 | 0.38 (0.35 to 0.40) | 1 |
| White Non-British | 340 515 | 7 | 63 | 4 | 0.19 (0.14 to 0.24) | 0.50 (0.39 to 0.64) |
| Pakistani | 180 265 | 4 | 33 | 2 | 0.18 (0.13 to 0.26) | 0.49 (0.35 to 0.69) |
| Indian | 132 646 | 3 | 19 | 1 | 0.14 (0.09 to 0.22) | 0.38 (0.24 to 0.60) |
| Bangladeshi | 62 944 | 1 | 10 | 1 | 0.16 (0.08 to 0.29) | 0.42 (0.23 to 0.79) |
| Black African | 154 071 | 3 | 37 | 2 | 0.24 (0.17 to 0.33) | 0.64 (0.46 to 0.89) |
| Mixed Black-African-White | 29 313 | 1 | 17 | 1 | 0.58 (0.34 to 0.93) | 1.55 (0.96 to 2.50) |
| Black Caribbean | 47 503 | 1 | 31 | 2 | 0.65 (0.44 to 0.93) | 1.73 (1.21 to 2.47) |
| Mixed Black-Caribbean-White | 46 445 | 1 | 28 | 2 | 0.60 (0.40 to 0.87) | 1.62 (1.11 to 2.36) |
| Other/unspecific | 344 186 | 7 | 92 | 6 | 0.27 (0.22 to 0.33) | 0.72 (0.58 to 0.88) |
| Unstated | 287 732 | 6 | 100 | 6 | 0.35 (0.28 to 0.42) | 0.89 (0.73 to 1.10) |
| Parent marital/registration status | ||||||
| Within marriage (ref) | 2 499 006 | 54 | 388 | 25 | 0.16 (0.14 to 0.17) | 1 |
| Joint registration, same address | 1 398 905 | 30 | 570 | 37 | 0.41 (0.37 to 0.44) | 2.64 (2.32 to 3.01) |
| Joint registration, different addresses | 450 482 | 10 | 309 | 20 | 0.69 (0.61 to 0.77) | 4.46 (3.84 to 5.18) |
| Sole registration | 286 371 | 6 | 292 | 19 | 1.02 (0.91 to 1.14) | 6.55 (5.63 to 7.62) |
| Mother country of birth | ||||||
| Non-UK (ref) | 1 127 462 | 24 | 190 | 12 | 0.17 (0.15 to 0.19) | 1 |
| UK | 3 507 302 | 76 | 1369 | 88 | 0.39 (0.37 to 0.41) | 2.30 (1.98 to 2.68) |
| Deprivation, IMD 5ths | ||||||
| 1=Advantaged (ref) | 708 738 | 15 | 109 | 7 | 0.15 (0.13 to 0.19) | 1 |
| 2 | 771 227 | 17 | 152 | 10 | 0.20 (0.17 to 0.23) | 1.28 (1.00 to 1.64) |
| 3 | 862 148 | 19 | 231 | 15 | 0.27 (0.23 to 0.30) | 1.75 (1.39 to 2.20) |
| 4 | 1 031 689 | 22 | 399 | 26 | 0.39 (0.35 to 0.43) | 2.53 (2.04 to 3.12) |
| 5=Disadvantaged | 1 260 962 | 27 | 668 | 43 | 0.53 (0.49 to 0.57) | 3.46 (2.82 to 4.23) |
| Gestation, weeks | ||||||
| 37+ (ref) | 4 376 271 | 94 | 1269 | 81 | 0.29 (0.27 to 0.31) | 1 |
| 32–36 | 217 808 | 5 | 224 | 14 | 1.03 (0.90 to 1.17) | 3.54 (3.07 to 4.08) |
| 22–31 | 40 685 | 1 | 66 | 4 | 1.62 (1.25 to 2.06) | 5.57 (4.35 to 7.13) |
| Mother age, years | ||||||
| 30+ (ref) | 2 206 398 | 48 | 429 | 28 | 0.19 (0.18 to 0.21) | 1 |
| 25–29 | 1 265 682 | 27 | 393 | 25 | 0.31 (0.28 to 0.34) | 1.60 (1.39 to 1.83) |
| 20–24 | 886 825 | 19 | 465 | 30 | 0.52 (0.48 to 0.57) | 2.69 (2.36 to 3.07) |
| <20 | 275 859 | 6 | 272 | 17 | 0.99 (0.87 to 1.11) | 5.03 (4.32 to 5.85) |
| Sex | ||||||
| Girl (ref) | 2 257 086 | 49 | 617 | 40 | 0.27 (0.25 to 0.30) | 1 |
| Boy | 2 377 678 | 51 | 942 | 60 | 0.40 (0.37 to 0.42) | 1.45 (1.31 to 1.60) |
| Total | 4 634 764 | 100 | 1559 | 100 | 0.34 (0.32 to 0.35) | – |
Number of live births (N, %); number of unexplained infant deaths (n, %); crude rate per 1000 live singleton births with 95% CI by ethnic group and other factors; OR relative to reference category (adjusted only for birth year). ORs shown in bold have CIs that do not include 1. Likelihood ratio test for ethnic variation (adjusted only for birth year): χ2(10 df)=113.6, p<0.0005.
IMD, Index of Multiple Deprivation.