Table 4 Standardised mortality ratios (SMR), 95% confidence intervals (CI) and observed deaths (O) by employment duration among production workers at three North Carolina asbestos textile plants, 1950–2003
Employment duration (years)
<11–<55–<1010–<20⩾20
OSMR (95% CI)OSMR (95% CI)OSMR (95% CI)OSMR (95% CI)OSMR (95% CI)
Lung cancer
1071.82 (1.50 to 2.19)711.86 (1.45 to 2.34)362.06 (1.44 to 2.85)312.34 (1.59 to 3.32)242.50 (1.60 to 3.72)
Pleural cancer and mesothelioma combined
0E = 0.31*210.52 (6.63 to 24.7)3†37.78 (25.06 to 75.19)1‡16.03 (9.29 to 54.17)2‡46.7 (29.4 to 110)
Pneumoconiosis
151.75 (0.98 to 2.89)71.28 (0.51 to 2.63)165.72 (3.27 to 9.29)177.32 (4.26 to 11.7)189.92 (5.88 to 15.7)
  • *Where the observed number of deaths is 0, the expected number is reported in place of the SMR and CI; †category includes two deaths coded to mesothelioma; ‡category includes one death coded to mesothelioma.