Colon and rectal cancer incidence and water trihalomethane concentrations in New South Wales, Australia

BMC Cancer

Table 3 Sensitivity analyses for the model of incidence rate ratios for colorectal cancer per IQR ¹ increase in concentration of total THMs and selected specific THM species after adjusting for the covariates mentioned in Table 2

THM species	Sex	Average exposure²	IRSD excluded	Restricted to SWC area	Spatial random effect excluded	Variance of THMs added
Total THM	Male	1.033 (0.954, 1.119)	1.018 (0.993, 1.041)	1.018 (0.993, 1.041)	1.019 (0.997, 1.042)	1.007 (0.979, 1.032)
Chloroform	Male	1.022 (0.946, 1.110)	1.008 (0.985, 1.031)	1.008 (0.985, 1.031)	1.011 (0.990, 1.034)	1.005 (0.982, 1.029)
Bromoform	Male	1.064 (1.021, 1.113)	1.025 (1.011, 1.040)	1.025 (1.011, 1.040)	1.026 (1.011, 1.041)	1.020 (1.005, 1.036)
BDCM	Male	1.031 (0.973, 1.102)	1.022 (0.995, 1.050)	1.022 (0.995, 1.050)	1.021 (0.996, 1.046)	1.008 (0.980, 1.039)
DBCM	Male	0.998 (0.956, 1.042)	1.028 (0.999, 1.058)	1.028 (0.999, 1.058)	1.012 (0.988, 1.038)	1.000 (0.975, 1.029)
Total THM	Female	0.986 (0.919, 1.056)	0.973 (0.948, 0.999)	0.973 (0.948, 0.999)	0.980 (0.957, 1.004)	0.970 (0.945, 0.994)
Chloroform	Female	1.004 (0.930, 1.087)	0.974 (0.950, 0.997)	0.974 (0.950, 0.997)	0.980 (0.957, 1.004)	0.979 (0.951, 1.006)
Bromoform	Female	1.008 (0.965, 1.050)	1.005 (0.989, 1.023)	1.005 (0.989, 1.023)	1.004 (0.987, 1.020)	1.005 (0.985, 1.023)
BDCM	Female	0.992 (0.937, 1.045)	0.976 (0.948, 1.005)	0.976 (0.948, 1.005)	0.981 (0.957, 1.006)	0.973 (0.938, 1.007)
DBCM	Female	0.982 (0.942, 1.020)	0.997 (0.964, 1.028)	0.997 (0.964, 1.028)	0.995 (0.971, 1.021)	0.995 (0.966, 1.023)

¹IQR: Total THM = 29 _g/L, Chloroform = 22 _g/L, Bromoform = 2 _g/L, BDCM = 6 _g/L and DBCM = 4 _g/L.
Note that the IQR values have been rounded to estimate IRR for ease of interpretation.
²Exposure averaged for all relevant years of the study.

ISSN: 1471-2407