Fig. 3

Plasma p-tau217 concentrations in different pre-analytical sample handling conditions. P-tau217 concentrations in EDTA plasma samples that were thawed at RT and analyzed without centrifugation (Cond 1), thawed at RT and centrifuged before the analysis (Cond 2), thawed on ice and analyzed without centrifugation (Cond 3), thawed on ice and centrifuged before analysis (Cond 4). Plasma samples were collected from (a) 50 Aβ⁻ and (b) 50 Aβ⁺ participants. P-values are from the two-way ANOVA repeated measures with FDR correction for multiple comparisons, boxes show interquartile range, the horizontal lines are the medians, and the whiskers are plotted using the Tukey method. Abbreviations: Aβ⁺, amyloid-β positive; Aβ⁻, amyloid-β negative; EDTA, ethylenediaminetetraacetic acid; RT, room temperature; NC, non-centrifugation; C, centrifugation