Table 6 Missing data on NHS number or postcode by data year | 1998–2003 (n = 99,200) | 2004–2009 (n = 128,666) | 2010–2015 (n = 189,373) |
|---|
| n | NHS number (%) | Postcode (%) | n | NHS number (%) | Postcode (%) | n | NHS number (%) | Postcode (%) |
|---|
| % missing |
| Age |
| 0–3 | 68,225 | 61.2 | 19.0 | 77,270 | 6.5 | 41.3 | 89,896 | 0.7 | 47.3 |
| 4–7 | 17,774 | 17.5 | 2.6 | 13,112 | 4.5 | 2.9 | 13,435 | 1.7 | 2.8 |
| 8–11 | 13,221 | 10.8 | 4.0 | 11,833 | 4.4 | 4.1 | 10,309 | 1.2 | 2.0 |
| 12–15 | | | | 15,370 | 4.7 | 4.0 | 14,144 | 1.5 | 3.7 |
| 16–19 | | | | 11,081 | 3.4 | 3.8 | 24,304 | 1.9 | 4.0 |
| 20–23 | | | | | | | 37,285 | 1.8 | 3.9 |
| Sex |
| Missing | 278 | 46.8 | 10.4 | 27 | 59.3 | 37.0 | 45 | 6.7 | 24.4 |
| Male | 43,996 | 48.7 | 15.2 | 60,181 | 5.9 | 27.3 | 99,675 | 1.1 | 22.8 |
| Female | 54,946 | 45.0 | 13.1 | 68,458 | 5.3 | 25.4 | 89,653 | 1.4 | 26.0 |
| Ethnic group |
| Missing | 51,188 | 52.9 | 16.2 | 26,669 | 7.9 | 36.4 | 17,133 | 3.1 | 21.0 |
| White | 40,263 | 37.8 | 12.0 | 83,078 | 4.6 | 22.4 | 137,015 | 0.8 | 23.5 |
| Mixed | 142 | 16.9 | 2.8 | 2,698 | 5.5 | 27.2 | 6,078 | 1.2 | 34.0 |
| Asian | 3,399 | 42.1 | 8.6 | 8,812 | 6.0 | 28.2 | 15,461 | 1.5 | 29.8 |
| Black | 1,807 | 55.0 | 6.9 | 4,804 | 7.9 | 31.1 | 8,029 | 1.9 | 26.3 |
| Chinese/Other | 2,421 | 62.4 | 17.1 | 2,605 | 10.1 | 30.2 | 5,657 | 3.8 | 25.8 |
| Socio-economic group |
| Missing | 13,937 | 65.7 | | 33,808 | 6.7 | | 46,042 | 0.7 | |
| Low deprivation | 59,914 | 43.5 | | 67,485 | 4.8 | | 100,721 | 1.0 | |
| High deprivation | 25,122 | 43.2 | | 26,851 | 5.0 | | 41,600 | 1.3 | |
| Foreign | 236 | 80.9 | | 401 | 81.0 | | 862 | 53.8 | |
| No fixed abode | 11 | 45.5 | | 121 | 20.7 | | 148 | 12.8 | |