Table 1. Characteristics of the Study Groups.

Group	No. of Patients	Male/Female	Median (IQR)
			Age at Lumbar Puncture, y	CSF Conservation Time, mo
ALS	94	64/30	62.5 (52.3-70.0)	42.0 (25.0-57.5)
Control	44	24/20	54.0 (37.0-69.3)	40.0 (34.0-53.0)
FTD	20	8/12	65.0 (61.0-72.3)	37.0 (7.5-65.8)
MNs	18	14/4	63.0 (57.0-71.5)	39.5 (14.3-48.5)
P value across groups	NA	.04a	.009b	.54

Abbreviations: ALS, amyotrophic lateral sclerosis; CSF, cerebrospinal fluid; FTD, frontotemporal dementia; IQR, interquartile range; MNs, motor neuropathies; NA, not applicable.

^aP ≤ .05.

^bP ≤ .01.