MAPT and early-onset autosomal dominant Alzheimer disease: Allowing for hemispheric laterality generally yielded CVR biomarkers with slightly improved SSE (5–30% smaller), which seems to concur with a previous finding of laterality of tau pathology accumulation in Alzheimer’s disease.35 In addition to the volume-weighted composite SUV that is used in previous SUVR studies on statistical ROIs,12-16 we considered a regional mean SUV, remarkably finding that the regional mean produced CVR biomarkers with better repeatability error (7–48% smaller) and SSE (35–60% smaller).