Table 3.

Regression estimates of the excess relative rate (ERR) of lung cancer mortality per 100 working level months (WLMs) with effect modification by attained age, age at exposure, and exposure rate. Pooled Uranium Miners Analysis (PUMA) of uranium miners in Canada, Czech Republic, France, Germany, and the United States, male miners hired in 1960 or later.

Parameters	Estimate	95% CI
ERR/100 WLM	8.38	(3.30, 18.99)
Age at exposure (y)
$\ge 35$	1	—
$<35$	0.59	(0.30, 1.20)
Attained age (y)
$<55$	1	—
55–64	0.55	(0.24, 1.30)
65–74	0.20	(0.06, 0.53)
$\ge 75$	0.14	(n.d., 0.64)
Exposure rate (WL)
$<0.5$	1	—
0.5–$<1$	1.23	(0.49, 2.77)
$\ge 1$	0.33	(0.13, 0.75)

Note: Background stratified by attained age, calendar period, study cohort, and duration of employment as a uranium miner. —, not applicable; CI, confidence interval; n.d., lower bound not determined; WL, working level.