Mortality from lung cancer and from all causes in nickel refinery workers (n = 812), by period from commencing employment and by period of commencing employment, 1958–2000
| Cause of death | Variable with levels | Obs | Exp† | SMR | (95% CI) | Statistical evaluation |
|---|---|---|---|---|---|---|
| *p<0.05. | ||||||
| †Based on mortality rates for England and Wales. | ||||||
| Period from commencing employment (y) | ||||||
| Lung cancer | 5–9 | 1 | 0.8 | 133 | – | het., p = 0.21 trend, p = 0.07 |
| 10–19 | 1 | 3.6 | 28 | – | ||
| 20–29 | 10 | 7.2 | 138 | (66 to 254) | ||
| ⩾30 | 16 | 8.6 | 186* | (106 to 301) | ||
| Total | 28 | 20.2 | 139 | (92 to 201) | ||
| All causes | 5–9 | 5 | 10.1 | 49 | (16 to 115) | het., p = 0.19 trend, p = 0.09 |
| 10–19 | 27 | 35.3 | 77 | (50 to 111) | ||
| 20–29 | 70 | 65.3 | 107 | (84 to 135) | ||
| ⩾30 | 89 | 87.6 | 102 | (83 to 111) | ||
| Total | 191 | 198.3 | 96 | (83 to 111) | ||
| Year of commencing employment | ||||||
| Lung cancer | 1953–62 | 18 | 13.2 | 137 | (81 to 216) | het., p = 0.62 trend, p = 0.84 |
| 1963–72 | 10 | 6.4 | 156 | (75 to 286) | ||
| 1973–92 | 0 | 0.6 | 0 | – | ||
| All causes | 1953–62 | 123 | 126.8 | 97 | (81 to 116) | het., p = 0.47 trend, p = 0.60 |
| 1963–72 | 64 | 64.1 | 100 | (77 to 128) | ||
| 1973–92 | 4 | 7.5 | 53 | (15 to 137) | ||