Table 1.

Demographic and clinical characteristics of study participants. Table entries are percentages, unless otherwise indicated.

		Cases (n=241)	Controls (n=597)
Diagnosis	Definite/probable ALS	74.7	-
	Possible ALS	10.0	-
	Lower motor neuron symptoms only (PMA)	15.4	-
Median time from symptom onset to diagnosis (months)		10.0	-
Median survival from diagnosis (months)		22.0	-
Male		97.9	94.1
Age (at diagnosis for cases, at interview for controls): Mean (SD)		62.4 (10.3)	61.7 (10.6)
Race/ethnicity	Non-Hispanic White	94.6	88.4
	Non-Hispanic Black	2.5	4.5
	Hispanic	0.4	3.5
	Multiple	2.1	1.8
	Other/unknown	0.4	1.7
Use of VA health care#		42.7	40.0
Application for VA benefits#		79.7	84.6
Education	High school or less	38.6	32.2
	More than high school, less than college degree	22.4	23.6
	College degree or more	39.0	44.2
Years of schooling: Mean (SD)		14.9 (2.8)	15.3 (3.2)
Branch with longest service	Air Force	22.8	22.4
	Army	41.1	33.5
	Marines	9.5	8.4
	Navy	18.7	18.8
	Coast Guard	0.8	1.2
	Activated Reserves	2.9	4.4
	Activated Guard	1.2	3.0
	Other	2.5	8.4
Years of service: Mean (SD)		8.2 (9.4)	9.7 (9.1)
Deployment	World War II	3.7	2.0
	Korea	5.4	6.0
	Vietnam	26.1	29.8
	Persian Gulf War	2.1	2.0
	Not deployed to any of the above conflicts	59.8	60.3

^#Prior to diagnosis for cases; prior to interview for controls.