. Author manuscript; available in PMC: 2013 Oct 1.

Published in final edited form as: Neurotoxicology. 2012 Sep 3;33(5):10.1016/j.neuro.2012.08.011. doi: 10.1016/j.neuro.2012.08.011

Table 3.

Prevalence ratios (PRs) for parkinsonism in relation to duration of employment and total welding exposure-years.

	n			PR (95% CI)^a		PR (95% CI)^b
	UPDRS3			UPDRS3		UPDRS3
	≥15	≥6 to <15	<6	≥15 vs. <6	≥6 to <15 vs. <6	≥15 vs. <6	≥6 to <15 vs. <6
Total weighted welding exposure-years^c
<1.0	14	65	58	Reference	Reference	Reference	Reference
1.0–3.4	28	78	59	1.7 (0.9–2.9)	1.0 (0.9–1.1)	1.4 (0.8–2.4)	1.0 (0.9–1.1)
3.4–8.8	38	97	59	2.0 (1.2–3.4)	1.1 (1.0–1.1)	1.4 (0.9–2.3)	1.0 (0.9–1.1)
≥8.8	32	129	59	1.8 (1.0–3.1)	1.1 (1.0–1.2)	1.0 (0.6–1.6)	1.0 (0.9–1.1)
p-trend						0.08	0.76

Crude estimates.

Adjusted for age at examination, gender, examining neurologist, and days since last occupational welding exposure; analyses restricted to workers from welding worksites.

Weighted by job category and title.