Effect of human variability on independent double reading in screening mammography.

RATIONALE AND OBJECTIVES

To demonstrate the range of gains and losses that radiologists might experience from independent double reading in screening mammography.

METHODS

From a national random sample of radiologists, the authors formed 131 pairs. For each radiologist, the authors analyzed the increase relative to his or her individual true-positive rate (TPR) or false-positive rate (FPR), number of additional cancers detected, and change to negative biopsy rate that would result from independent double reading after pairing.

RESULTS

The average radiologist can expect an 8%-14% gain in TPR and a 4%-10% increase in FPR with pairing. For some radiologists, double reading increased the TPR with a small concomitant increase in FPR. Other radiologists, however, realized small gains in TPR with large increases in FPR. Adding the reading from a more experienced radiologist did not necessarily improve the TPR of a radiologist with less experience.

CONCLUSION

Radiologists can form complementary and noncomplementary pairs for double reading. Use of this procedure must be decided on an individual basis.