. 2017 Nov 6;74(12):1492–1501. doi: 10.1001/jamaneurol.2017.2814

Table 1. Correlations Between Aβs Measured Using MS and Different Immunoassays^a.

Immunoassay	MS-Derived Aβ42 Level	MS-Derived Aβ42:Aβ40 Ratio
Classic Aβ42-INNOTEST
Pearson correlation	r = 0.88	r = 0.87
Spearman correlation	ρ = 0.91	ρ = 0.88
Modified Aβ42-INNOTEST
Pearson correlation	r = 0.97	r = 0.70^b
Spearman correlation	ρ = 0.96^b	ρ = 0.74^b
Aβ42-FL
Pearson correlation	r = 0.93^c	r = 0.64^b
Spearman correlation	ρ = 0.92	ρ = 0.70^b
Aβ42-EI
Pearson correlation	r = 0.93^d	r = 0.73^b
Spearman correlation	ρ = 0.95^d	ρ = 0.78^b
Aβ42-MSD
Pearson correlation	r = 0.95^b	r = 0.74^b
Spearman correlation	ρ = 0.96^b	ρ = 0.78^b

Abbreviations: Aβ, amyloid β; EI, EUROIMMUN; FL, fully automated Lumipulse; MS, mass spectrometry; MSD, Meso Scale Discovery.

^{^a}

P < .001 for all comparisons except P = .02 for the correlation between MS-derived Aβ42 and Aβ42-INC:Aβ40 ratio. Differences between the correlation coefficients were estimated using the Meng test.

^{^b}

P < .001 compared with classic Aβ42-INNOTEST.

^{^c}

P = .01 compared with classic Aβ42-INNOTEST.

^{^d}

P < .01 compared with classic Aβ42-INNOTEST.

Table 1. Correlations Between Aβs Measured Using MS and Different Immunoassaysa.

Table 1. Correlations Between Aβs Measured Using MS and Different Immunoassays^a.