Cross-lagged panel model results in a subgroup of HC subjects who are Aβ−. PET-derived Aβ burden, CSF p-tau concentrations, and CSF Aβ42 concentrations are modeled across three waves (baseline, 24 months, and 48 months) with covariates sex, baseline age, baseline MMSE score, APOEε4, and baseline whole-brain atrophy. The complete covariance and correlation matrices are provided in Figure 3-1 and Figure 3-2. Figure legend as described in Figure 2.