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One-shot estimate of MRMC variance: AUC
1NIBIB/CDRH Laboratory for the Assessment of Medical Imaging Systems, US FDA/CDRH, Bldg 1, HFZ-140, 12720 Twinbrook Parkway (Rm 158), Rockville MD 20852-1720, USA. brandon.gallas@fda.hhs.gov
Academic Radiology
|February 21, 2006
Summary
A new unbiased "one-shot" method estimates the variance of reader-averaged AUC without resampling. This method performs comparably to existing techniques, offering improved efficiency with fewer cases.
Area of Science:
- Medical imaging analysis
- Statistical modeling in diagnostics
Background:
- Estimating the area under the receiver operating characteristic curve (AUC) often uses a fully crossed design where multiple readers evaluate multiple cases.
- The variability in reader-averaged AUC stems from multiple readers and multiple cases (MRMC).
Purpose of the Study:
- To present a novel, unbiased, nonparametric estimate for the variance of the reader-averaged AUC.
- To introduce a method that does not rely on resampling tools, termed the "one-shot" estimate.
Main Methods:
- The one-shot estimate is derived from MRMC variance and nonparametric AUC variance literature.
- Monte Carlo simulations with model observers and varied image/noise parameters were used to assess bias and variance.
- Comparison was made against the jackknife resampling technique.
Main Results:
- The one-shot estimator demonstrated similar performance to the jackknife estimator.
- The one-shot method showed marginally higher efficiency when the number of cases was small.
Conclusions:
- A new, unbiased "one-shot" estimate for MRMC variance of AUC has been developed.
- The method is based on a probabilistic foundation with limited assumptions and compares favorably to established estimates.
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