NCT02107599 - The Feasibility of Florbetapir Quantitation in Europe | Crick

Overview

This study will evaluate whether the addition of quantitation as an adjunct to visual interpretations significantly improves the accuracy of Amyvid scan interpretation.

Study Type

INTERVENTIONAL

Allocation

NA

Purpose

DIAGNOSTIC

Masking

SINGLE

Enrollment

96

Conditions

Alzheimer's Disease

Interventions

Florbetapir (18F)DRUG

No Florbetapir (18F) will be administered in this study.

Eligibility

Sex: ALL

Medical Language ↔ Plain English

Inclusion Criteria: * Readers have undergone Amyvid reader training * Readers have not more than minimal experience with quantitation of amyloid PET scans Exclusion Criteria: * Readers have previously been trained to quantitate amyloid PET scans

Locations (1)

Research Site

Leiden, Netherlands

Outcomes

Primary Outcomes

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.

Time frame: Scan acquired 50-60 minutes post injection

Secondary Outcomes

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.

Time frame: Scan acquired 50-60 minutes post injection