Editors' Pick Taking the A Train? Limited Consistency of Aβ42 and the Aβ42/40 Ratio in the AT(N) Classification. Gouilly D, Tisserand C, Nogueira L, Saint-Lary L, Rousseau V, Benaiteau M, Rafiq M, Carlier J, Milongo-Rigal E, Pagès J-C, et al. J Alzheimers Dis. 2021 Sep 28; 83(3):1033-1038. PMID: 34397413. Abstract