Table 2.

Comparison of ALS diagnosis criteria and insurance for matched and unmatched cases.

Unmatched			Matched			Chi-square
El Escorial criteria						65.79, p<0.00001
Definite	961	46.9%	Definite	1460	53.7%
Probable	430	21.0%	Probable	603	22.2%
Probable + Lab	165	8.1%	Probable + Lab	254	9.3%
Possible	358	17.5%	Possible	290	10.7%
Unclassified	133	6.5%	Unclassified	113	4.2%
Total	2047		Total	2720
Combined El Escorial criteria						47.63, p<0.00001
Definite + Probable	1556	76.0%	Definite + Probable	2317	85.2%
Possible + Unclassified	491	24.0%	Possible + Unclassified	403	14.8%
Total	2047		Total	2720
Medicare						359.82, p<0.00001
Yes	788	38.5%	Yes	1799	66.1%
No	1236	60.4%	No	902	33.2%
Unknown	23	1.1%	Unknown	19	0.7%
Total	2047		Total	2720
Veterans Administration (VA)						3.54, p = 0.17
Yes	116	5.7%	Yes	175	6.4%
No	1908	93.2%	No	2526	92.9%
Unknown	23	1.1%	Unknown	19	0.7%
Total	2047		Total	2720
Private Insurance						3.14, p = 0.21
Yes	898	43.9%	Yes	1232	45.3%
No	1126	55.0%	No	1469	54.0%
Unknown	23	1.1%	Unknown	19	0.7%
Total	2047		Total	2720