Performance of plasma Aβ42/40, measured using a fully automated immunoassay, across a broad patient population in identifying amyloid status.

"Declarations Ethics approval and consent to participateThe Certified Review Board of Keio University (#N20170237) approved the study design and protocol. The study was conducted in accordance with the Declaration of Helsinki. All participants (plus their proxies as needed) provided written informed consent for participation in the study. The study was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; https://www.umin.ac.jp/ctr/index.htm, ID# UMIN000032027) and Japan Registry of Clinical Trials (jRCT; https://jrct.niph.go.jp/, ID# jRCTs031180225). Consent for publicationNot applicable. Competing interestsAuthor YS is employed by Eisai Co., Ltd. The remaining authors report no competing interests. Competing interests Author YS is employed by Eisai Co., Ltd. The remaining authors report no competing interests."

"Funding This research was supported by Japan Agency for Medical Research and Development (AMED) under Grant Number 17pc0101006. The fund was initially awarded to EISAI Co., Ltd. (https://www.eisai.com/index.html). Part of the fund was re-awarded to Keio University School of Medicine. AMED and EISAI were not involved in the study design, data collection, analyses, or preparation of the manuscript, except for the partial involvement of author YS in the plasma biomarker measurement."