Trial Outcomes & Findings for Evaluation of Web-based Training to Educate Physicians in the Methods of Interpreting Florbetapir-PET Scans (NCT NCT01550549)
NCT ID: NCT01550549
Last Updated: 2012-06-07
Results Overview
Measure of agreement among five readers using a binary read method (amyloid positive/negative) calculated using Fleiss' kappa. All scans were read in a blinded fashion without access to clinical information.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
151 participants
Primary outcome timeframe
Scan acquired 50-60 min post-injection
Results posted on
2012-06-07
Participant Flow
NO SUBJECTS WERE ENROLLED IN THIS STUDY - this study re-read scans obtained in other clinical studies
Participant milestones
| Measure |
Florbetapir-PET Scans
All subject scans with a valid florbetapir-PET scan
|
|---|---|
|
Overall Study
STARTED
|
151
|
|
Overall Study
COMPLETED
|
151
|
|
Overall Study
NOT COMPLETED
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Evaluation of Web-based Training to Educate Physicians in the Methods of Interpreting Florbetapir-PET Scans
Baseline characteristics by cohort
| Measure |
Florbetapir-PET Scans
n=151 Participants
All subjects with a valid florbetapir-PET scan (59 from study A07/A16 and 92 from study A05)
|
|---|---|
|
Age Continuous
|
74.9 years
STANDARD_DEVIATION 11.87 • n=5 Participants
|
|
Sex: Female, Male
Female
|
75 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
76 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
151 participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Scan acquired 50-60 min post-injectionPopulation: 59 autopsy subjects (study A07\[NCT00857415\]/A16\[NCT01447719\]) + 20 healthy controls + 20 mild cognitive impairment + 20 AD (from study A05\[NCT00702143\])
Measure of agreement among five readers using a binary read method (amyloid positive/negative) calculated using Fleiss' kappa. All scans were read in a blinded fashion without access to clinical information.
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=119 Participants
|
Autopsy Within One Year of Scan
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Inter-rater Reliability
|
0.81 kappa statistic
Interval 0.75 to 0.87
|
—
|
SECONDARY outcome
Timeframe: at autopsy, within 2 years of scanCalculated as the percent of true positives which are correctly identified
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=59 Participants
|
Autopsy Within One Year of Scan
n=46 Participants
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Sensitivity of Florbetapir-PET to Detect Moderate to Frequent Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 1
|
79 percentage of positive cases IDed
Interval 64.5 to 89.2
|
86 percentage of positive cases IDed
Interval 68.5 to 94.3
|
|
Sensitivity of Florbetapir-PET to Detect Moderate to Frequent Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 2
|
92 percentage of positive cases IDed
Interval 79.7 to 97.3
|
100 percentage of positive cases IDed
Interval 87.9 to 100.0
|
|
Sensitivity of Florbetapir-PET to Detect Moderate to Frequent Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 3
|
69 percentage of positive cases IDed
Interval 53.6 to 81.4
|
75 percentage of positive cases IDed
Interval 56.6 to 87.3
|
|
Sensitivity of Florbetapir-PET to Detect Moderate to Frequent Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 4
|
87 percentage of positive cases IDed
Interval 73.3 to 94.4
|
93 percentage of positive cases IDed
Interval 77.4 to 98.0
|
|
Sensitivity of Florbetapir-PET to Detect Moderate to Frequent Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 5
|
82 percentage of positive cases IDed
Interval 67.3 to 91.0
|
89 percentage of positive cases IDed
Interval 72.8 to 96.3
|
SECONDARY outcome
Timeframe: at autopsy, within 2 years of scanCalculated as the percent of true negatives which are correctly identified
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=59 Participants
|
Autopsy Within One Year of Scan
n=46 Participants
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Specificity of Florbetapir-PET to Detect no or Sparse Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 1
|
90 percentage of negative cases IDed
Interval 69.9 to 97.2
|
89 percentage of negative cases IDed
Interval 67.2 to 96.9
|
|
Specificity of Florbetapir-PET to Detect no or Sparse Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 2
|
90 percentage of negative cases IDed
Interval 69.9 to 97.2
|
89 percentage of negative cases IDed
Interval 67.2 to 96.9
|
|
Specificity of Florbetapir-PET to Detect no or Sparse Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 3
|
95 percentage of negative cases IDed
Interval 76.4 to 99.1
|
94 percentage of negative cases IDed
Interval 74.2 to 99.0
|
|
Specificity of Florbetapir-PET to Detect no or Sparse Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 4
|
95 percentage of negative cases IDed
Interval 76.4 to 99.1
|
94 percentage of negative cases IDed
Interval 74.2 to 99.0
|
|
Specificity of Florbetapir-PET to Detect no or Sparse Beta-amyloid Neuritic Plaques (Probable/Definite Alzheimer's Disease)
Reader 5
|
95 percentage of negative cases IDed
Interval 76.4 to 99.1
|
100 percentage of negative cases IDed
Interval 82.4 to 100.0
|
POST_HOC outcome
Timeframe: Scan acquired 50-60 min post-injectionPopulation: 59 from study A07(NCT00857415)/A16(NCT01447719) and 92 from study A05(NCT00702143)
Measure of agreement among multiple readers using binary read method (Fleiss' kappa). Where available, histopathology analysis at autopsy was the truth standard (TS).
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=151 Participants
|
Autopsy Within One Year of Scan
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Inter-reader Reliability
All subjects [n=151]
|
0.83 kappa statistic
Interval 0.78 to 0.88
|
—
|
|
Inter-reader Reliability
All subjects with a TS [n=59]
|
0.75 kappa statistic
Interval 0.67 to 0.83
|
—
|
|
Inter-reader Reliability
All subjects without a TS [n=92]
|
0.88 kappa statistic
Interval 0.82 to 0.94
|
—
|
|
Inter-reader Reliability
AD [n=49] (29 with TS; 20 no TS)
|
0.67 kappa statistic
Interval 0.58 to 0.76
|
—
|
|
Inter-reader Reliability
MCI [n=57] (5 with TS; 52 no TS)
|
0.91 kappa statistic
Interval 0.83 to 0.99
|
—
|
|
Inter-reader Reliability
Cognitively normal without TS [n=20]
|
0.83 kappa statistic
Interval 0.69 to 0.97
|
—
|
|
Inter-reader Reliability
Cognitively normal with TS [n=12]
|
0.73 kappa statistic
Interval 0.55 to 0.87
|
—
|
|
Inter-reader Reliability
Other (non-AD) dementia with TS [n=13]
|
0.52 kappa statistic
Interval 0.35 to 0.69
|
—
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Baseline scanMedian sensitivity and specificity for 5 independent readers to detect moderate to frequent amyloid plaques (per CERAD criteria).
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=59 Participants
|
Autopsy Within One Year of Scan
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Median Sensitivity and Specificity vs. CERAD Diagnosis
Sensitivity
|
82 percentage of true positives/negatives
Interval 69.0 to 92.0
|
—
|
|
Median Sensitivity and Specificity vs. CERAD Diagnosis
Specificity
|
95 percentage of true positives/negatives
Interval 90.0 to 95.0
|
—
|
POST_HOC outcome
Timeframe: Baseline scanReader results (number of false negatives and number of false positives) for blinded independent readers. There were a total of 39 positive and 20 negative scans based on histopathology at autopsy.
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=59 Participants
|
Autopsy Within One Year of Scan
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Individual Reader Results (All Scans With Autopsy)
Reader 1 - False Negatives
|
8 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 1 - False Positives
|
2 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 2 - False Negatives
|
3 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 2 - False Positives
|
2 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 3 - False Negatives
|
12 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 3 - False Positives
|
1 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 4 - False Negatives
|
5 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 4 - False Positives
|
1 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 5 - False Negatives
|
7 florbetapir scans
|
—
|
|
Individual Reader Results (All Scans With Autopsy)
Reader 5 - False Positives
|
1 florbetapir scans
|
—
|
POST_HOC outcome
Timeframe: Baseline scanReader results (number of false negatives and number of false positives) for blinded independent readers. There were a total of 28 positive and 18 negative scans based on histopathology at autopsy.
Outcome measures
| Measure |
Florbetapir-PET Scans Primary Analysis Group
n=46 Participants
|
Autopsy Within One Year of Scan
Subjects with a valid florbetapir-PET scan and autopsy (only those who deceased less than 12 months after the scan)
|
|---|---|---|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 1 - False Negatives
|
4 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 1 - False Positives
|
2 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 2 - False Negatives
|
0 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 2 - False Positives
|
2 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 3 - False Negatives
|
7 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 3 - False Positives
|
1 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 4 - False Negatives
|
2 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 4 - False Positives
|
1 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 5 - False Negatives
|
3 florbetapir scans
|
—
|
|
Individual Reader Results (Autopsy Within 1 Year of Scan)
Reader 5 - False Positives
|
0 florbetapir scans
|
—
|
Adverse Events
Florbetapir-PET Scans
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place
Restriction type: GT60