Fully automated and highly specific plasma β-amyloid immunoassays predict β-amyloid status defined by amyloid positron emission tomography with high accuracy

Table 1 Participant demographics

	Discovery study (n = 197)	Validation study (n = 200)	P value
Age (years), mean ± SD	71.1 ± 8.5	70.8 ± 7.9	NS
Sex, female/male	112/85	99/101	NS
Race, White/Japanese/Other	130/50/17	136/50/14	NS
APOE ε4 status, − / + /NA	123/71/3	114/86/0	NS
Amyloid PET status, − / +	97/100	100/100	NS
Amyloid PET probe, FBB/FBP/FMM/NA	124/27/46/0	124/22/45/9	0.023
MMSE, mean ± SD	26.4 ± 1.8	26.5 ± 1.8	NS
CDR-SB, mean ± SD	2.4 ± 1.0	2.5 ± 1.0	NS
Centiloid unit, mean ± SD	38.4 ± 50.0 (n = 180)	41.4 ± 48.9 (n = 191)	NS
Clinical disease staging, MCI due to AD/mild AD	157/40	160/40	NS

Significant differences between the discovery and validation studies were evaluated via the Student’s t-test for continuous measures and the χ.² test for categorical variables
Abbreviations: PET Positron emission tomography, SD Standard deviation, NS Not significant, APOE Apolipoprotein E, NA not available, FBB Florbetaben, FBP Florbetapir, FMM Flutemetamol, MMSE Mini-Mental State Examination, CDR-SB Clinical Dementia Rating-Sum of Boxes, MCI Mild cognitive impairment, AD Alzheimer’s disease

ISSN: 1758-9193