Table 1. Demographic characteristics of study participants.

	Penn Udall Discovery Cohort		PDBP Replication Cohort (Penn State and UTSW)		Penn ALS	BioFIND
Disease group	PD	NC	PD	NC	ALS*	ON	OFF
Participants total	96	45	215	102	59	10
Female/Male	42/54	22/23	101/114	51/51	26/33	5/5
p-Value	0.59a		0.76c			N/A
Age at plasma sampling mean ± SD (years)	69.9 ± 7.52	70.2 ± 10.04	66.8 ± 8.6	66.1 ± 10.5	61.9 ± 10.5	73.5 ± 6.13
p-Value	0.65b		0.84e (PD versus NC)			N/A
			0.02e (ALS versus NC); 0.002e (ALS versus PD)
Collection site number	N/A	N/A	215	102	N/A	N/A
Penn State/UTSW			100/115	78/24
p-Value	N/A	N/A	< 0.01a		N/A	N/A
Blood samples storage at −80 °C mean ± SD (years)	1.44 ± 0.88	1.43 ± 1.53	3.62 ± 0.54	3.46 ± 0.72	5.15 ± 2.01	3.26 ± 0.76	3.24 ± 0.76
p-value	0.977d		0.33e (PD versus NC)			0.943d
			<0.001e (ALS versus PD and ALS versus NC)
Somalogic plate number	N/A	N/A	215	102	N/A	N/A
Batch 1/2/3/4/5			49/49/48/48/21	21/20/24/24/13
p-Value	N/A	N/A	0.88c		N/A	N/A
Baseline DRS (UPenn) or MoCA (UTSW) mean ± SD	136.95 ± 9.96	N/A	26.47 ± 2.58‡	N/A		N/A

^aFisher exact test.

^bMann-Whitney test.

^cChi-squared test.

^dt test.

^eTukey HSD test.

^‡ For 110 UTSW participants with PD considered for longitudinal analyses.

Abbreviations: ALS, amyotrophic lateral sclerosis; DRS, Mattis Dementia Rating Scale-2; HSD, honest significant difference; MoCA, Montreal Cognitive Assessment; NC, neurologically normal control; PD, Parkinson’s disease; PDBP, Parkinson’s Disease Biomarker Program; SD, standard deviation; UPenn, University of Pennsylvania; UTSW, University of Texas Southwestern Medical Center