Table 4 Standardized incidence ratios (SIR) and rate ratio (RR) trends for lung cancer among cotton textile production unit workers by dust exposure category.
Exposure category | Obs | SIR | 95% CI | RR | 95% CI | χ2 test for trend |
|---|---|---|---|---|---|---|
Male | ||||||
None* (N = 2511) | 42 | 1.01 | 0.73–1.36 | 1 (reference) | χ2 = 9.68;p = 0.02 | |
Low (N = 656) | 10 | 1.91 | 0.92–3.51 | 1.89 | 0.85–3.85 | |
Medium (N = 481) | 7 | 1.30 | 0.52–2.69 | 1.29 | 0.49–2.91 | |
High (N = 529) | 4 | 0.77 | 0.21–1.96 | 0.76 | 0.20–2.10 | |
Very high (N = 574) | 2 | 0.24 | 0.03–0.86 | 0.24 | 0.03–0.91 | |
Female | ||||||
None (N = 2140) | 2 | 0.92 | 0.11–3.30 | 1 (reference) | χ2 = 4.68;p = 0.20 | |
Low (N = 1350) | 3 | 2.38 | 0.49–6.91 | 2.58 | 0.30–30.9 | |
Medium (N = 1410) | 3 | 2.17 | 0.45–6.35 | 2.36 | 0.27–28.2 | |
High (N = 1371) | 2 | 1.28 | 0.16–4.63 | 1.39 | 0.10–19.2 | |
Very high (N = 1910) | 1 | 0.55 | 0.01–3.08 | 0.60 | 0.01–11.5 |