Table 5.

Excess relative rate (ERR) of solid cancer per gray for restricted 5-year lagged colon dose ranges in subsets of the Life Span Study and INWORKS

	Colon dosea ranges
	0–100 mGy	0–200 mGy	0–300 mGy	0–500 mGy	0–1000 mGy	Whole
Life Span Study
Mean colon dose	14.2	25.2	34.4	50.2	77.0	115.7
Person-years	1,158,870	1,266,440	1,320,560	1,382,440	1,442,100	1,480,340
Observed deaths	6069	6664	6973	7315	7686	7982
ERR/Gy	0.38	0.50	0.45	0.25	0.24	0.28
90% CI	−0.27; 1.07	0.17; 0.86	0.21; 0.70	0.11; 0.41	0.15; 0.34	0.18; 0.38
P (vs. null model)b	0.343	0.011	0.001	0.004	< 0.001	< 0.001
Fitted excess deathsc	45.0	116.8	146.8	128.0	191.4	321.1
INWORKS
Mean colon dose	9.4	12.8	14.5	15.9	16.3	16.4
Person-years	5,943,550	6,104,410	6,150,100	6,173,470	6,178,150	6,178,320
Observed deaths	15,094	15,832	16,079	16,235	16,278	16,279
ERR/Gy	0.49	0.63	0.32	0.26	0.31	0.29
90% CI	−0.21; 1.23	0.21; 1.07	0.01; 0.65	0.01; 0.52	0.09; 0.54	0.07; 0.53
P (vs. null model)b	0.253	0.012	0.092	0.091	0.021	0.026
Fitted excess deathsc	93.5	179.4	111.8	102.5	129.7	124.3

CI likelihood-based confidence interval

^aCumulative dose in INWORKS

^bLikelihood ratio test

^cUnder a linear ERR model (no modifying effect of age)

The LSS ERR and fitted excess estimates are weighted averages over sex with a weight of 0.88 for males and 0.12 for females; sex-averaged estimates for the restricted dose ranges were obtained by fixing the parameter for effect modification by sex to the value for that parameter obtained when fitting the model to the full-dose range