Figure 5.

Required Treatment Effect and Sample Size Calculations. Required treatment effect sizes are plotted against sample sizes in an 18-month trial for four enrichment schemes – black: screened for evidence of Aβ pathology but with variable tau progression; green: screened for evidence of Aβ pathology and stable tau profile; blue: screened for evidence of Aβ pathology and moderate tau accumulation profile; and red: screened for evidence of Aβ pathology and fast tau accumulation profile. The plotted curves show the combinations of the required treatment effect and sample size to achieve 80% power for clinical outcome measures of ADAS-Cog and CDR-SB and biomarker outcome measures of tau burden in the metaROI, Braak III, Braak IV, and Braak V regions.