1. A method for evaluating a prospective treatment for Alzheimer's disease (AD), the method comprising: receiving at a computing device a plurality of brain imaging measurements from an 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scanner, the brain imaging measurements indicating a cerebral metabolic rate for glucose (CMRgl) associated with each of a plurality of subjects in a treatment study, wherein the measurements are associated with a first voxel size; and executing instructions stored in memory of the computing device, wherein execution of the instructions by a processor of the computing device: resamples the brain imaging measurements with a second voxel size larger than the first voxel size to reduce a number of voxels of the measurements; transforms the brain imaging measurements into a voxel-based data matrix; partitions the data matrix into a plurality of sub-matrices; and reads the sub-matrices into memory of the computing device one at a time and iteratively: calculates based on a predetermined interval a rate of change in CMRgl for each of the subjects; compares the rates of change in CMRgl calculated for the subjects to rates of change associated with a plurality of untreated subjects; and determines that a difference between the rates of change in CMRgl of the subjects and the untreated subjects is statistically significant.