Fig. 2

a–e Passing Bablok regression analyses with 95% CI of core biomarkers measured in fresh CSF samples and after 1 month of deep-freezing. Correlations have been calculated in terms of Spearman’s correlation coefficients (ρ). Fitted slopes (α) and intercepts (β) with their 95% CI are also shown. f Mean relative differences of Aβ40, Aβ42, Aβ42/Aβ40, t-tau, and p-tau between fresh and frozen samples are plotted together. Boxes representing data distributions are centered on the mean values, with the internal horizontal line representing the median. Boxes heights are equal to the standard deviations of the relative differences while whiskers represent the 5–95% data range