Dichotomize participants based on ROI cutoff valuesSource:
Aizenstein et al. (2008) proposed a standardized method of calculating PIB+ cutoff values to classify participants as PIB+ or PIB-. They used the DVR from 7 ROIs associated with amyloid deposition. This function takes the ROI-based cutoff values, e.g. from cutoff_aiz(), and returns a table specifying which participants are positive, i.e. which have at least one ROI greater than the cutoff.
SUVR or DVR data for group of participants from batch_tm()
cutoffs for ROIs as from cutoff_aiz()
Aizenstein HJ, Nebes RD, Saxton JA, et al. 2008. Frequent amyloid deposition without significant cognitive impairment among the elderly. Arch Neurol 65: 1509-1517.
Other Cutoff functions: