The Feasibility of Florbetapir Quantitation in Europe

실험적: Physician Readers

Physician readers will interpret Amyvid scans using qualitative analysis followed by the use of quantitation. No subjects will be exposed to Florbetapir(18F) as part of this study.

의약품: 플로르베타피르 (18F)

본 연구에서는 플로르베타피르(18F)를 투여하지 않을 것입니다.

다른 이름들:

• 아미비드
• 18F-AV-45
• 플로르베타피르 F 18

Change in Reader Accuracy After Application of Quantitation Software

Evaluate whether the use of quantitation software improves florbetapir (18F) scan interpretation by using the net reclassification index (NRI). The NRI is a prospective measure that quantifies the correctness of upward and downward reclassification or movement of predicted probabilities as a result of adding a new marker. NRI Values >0 indicate an improvement in scan interpretation accuracy and values <0 indicate a decline in scan interpretation accuracy after application of quantitation software.

NRI = [P(up,event)-P(down,event)]-[P(up,nonevent)-P(down,nonevent)] Where P(up,event) = # events up/# events P(down,event) = # events down/# events P(up,nonevent) = # nonevents up/# nonevents P(down,nonevent) = # nonevents down/# nonevents and events: true positive case nonevents: true negative case up: scan change from negative to positive down: scan change from positive to negative

Only the 46 scans with autopsy from A16 are used for this outcome measure.

Change in Scan Interpretation Reliability After Application of Quantitation Software

Evaluate whether the use of quantitation software improves florbetapir (18F) scan interpretation by using the net reclassification index (NRI). The NRI is a prospective measure that quantifies the correctness of upward and downward reclassification or movement of predicted probabilities as a result of adding a new marker. NRI Values >0 indicate an improvement in scan interpretation accuracy and values <0 indicate a decline in scan interpretation accuracy after application of quantitation software.

NRI = [P(up,event)-P(down,event)]-[P(up,nonevent)-P(down,nonevent)] Where P(up,event) = # events up/# events P(down,event) = # events down/# events P(up,nonevent) = # nonevents up/# nonevents P(down,nonevent) = # nonevents down/# nonevents and events: true positive case nonevents: true negative case up: scan change from negative to positive down: scan change from positive to negative

Only the 46 scans with autopsy from A16 are used for this outcome measure.