Table 3. Analysis of morbidity (SIR) due to either myocardial infarction or stroke in the cohort.

Results are shown for the whole cohort and the cohort stratified by cumulative silica-exposure quartiles and employment length.

			Obs	Exp	SIR	95% CI
Myocardial	Totalt		311	309.6	1.00	0.9–1.1
Infarction
ICD10: I21-I22
	Quartz quartiles	<0.11	36	36.1	0.99	0.7–1.4
		0.11–0.25	75	57.3	1.31	1.0–1.6
		0.25–0.65	67	80.4	0.83	0.7–1.1
		>0.65	133	135.8	0.98	0.8–1.2
	Employment time(in years)	< = 2	36	36.2	0.99	0.7–1.4
		2.1–10	102	96.3	1.06	0.9–1.3
		10.1–20	73	69.8	1.05	0.8–1.3
		>20	100	107.2	0.93	0.8–1.1
Stroke	Totalt		327	243.5	1.34	1.2–1.5
ICD10: I61, I63, I64
	Quartz quartiles	<0.11	38	26.8	1.42	1.0–2.0
		0.11–0.25	64	43.3	1.48	1.1–1.9
		0.25–0.65	66	62.4	1.06	0.8–1.4
		>0.65	159	111.0	1.43	1.2–1.7
	Employment time(in years)	< = 2	43	27.4	1.60	1.1–2.1
		2.1–10	93	74.3	1.25	1.01–1.5
		10.1–20	73	55.3	1.32	1.04–1.7
		>20	118	86.6	1.36	1.1–1.6