A device for performing an amyloid assessment, the device comprising: a radiation detector assembly including at least one radiation detector; and at least one electronic processor programmed to: detect radiation counts over a data acquisition time interval using the radiation detector assembly; compute at least one current count metric from the detected radiation counts; store the at least one current count metric associated with a current test date in a non-transitory storage medium; and determine an amyloid metric based on a comparison of the at least one current count metric with a count metric stored in the non-transitory storage medium associated with an earlier test date; and wherein: the at least one current count metric includes at least one of a count rate and a total counts detected over the data acquisition time interval; and the computing of the at least one current count metric includes scaling the at least one current count metric by one or more of patient weight, patient age, patient gender, and patient ethnicity. a radiation detector assembly including at least one radiation detector; and at least one electronic processor programmed to: detect radiation counts over a data acquisition time interval using the radiation detector assembly; compute at least one current count metric from the detected radiation counts; store the at least one current count metric associated with a current test date in a non-transitory storage medium; and determine an amyloid metric based on a comparison of the at least one current count metric with a count metric stored in the non-transitory storage medium associated with an earlier test date; and wherein: the at least one current count metric includes at least one of a count rate and a total counts detected over the data acquisition time interval; and the computing of the at least one current count metric includes scaling the at least one current count metric by one or more of patient weight, patient age, patient gender, and patient ethnicity. detect radiation counts over a data acquisition time interval using the radiation detector assembly; compute at least one current count metric from the detected radiation counts; store the at least one current count metric associated with a current test date in a non-transitory storage medium; and determine an amyloid metric based on a comparison of the at least one current count metric with a count metric stored in the non-transitory storage medium associated with an earlier test date; and wherein: the at least one current count metric includes at least one of a count rate and a total counts detected over the data acquisition time interval; and the computing of the at least one current count metric includes scaling the at least one current count metric by one or more of patient weight, patient age, patient gender, and patient ethnicity. the at least one current count metric includes at least one of a count rate and a total counts detected over the data acquisition time interval; and the computing of the at least one current count metric includes scaling the at least one current count metric by one or more of patient weight, patient age, patient gender, and patient ethnicity.