This is higher compared with what has been reported using semiquantitative thresholds, which showed approximately 5%–10% tau positivity in Aβ-positive individuals.4,5 A potential explanation could be that our CU group partly consisted of individuals with SCD, which has been associated with increased risk of dementia.40 Moreover, it must be noted that the cohorts from which CU individuals were included were enriched for Aβ positivity.41 Over 2-year follow-up, none of the CU tau-negative participants (n = 46, of which 13 were Aβ positive) converted to tau-positive. This evidence concerns the gene MAPT and Schnyder corneal dystrophy.