Search and nonsearch protocols for radiographic consultation.

Six radiologists, acting as radiograph reviewers, used two different consultation protocols to differentiate among 292 ambiguous chest radiographic findings: 120 simulated nodules and 172 normal findings (previous readers' false-positive reports of nodules). The nonsearch protocol identified each finding (by film location), and reviewers rated the likelihood of each finding's being a pulmonary nodule. The search protocol asked reviewers to report and rate all locations regarded as possible nodules on each radiograph and assigned a default negative rating to any unreported finding (nodule or normal structure). Receiver operating characteristic analyses demonstrated a significantly higher accuracy for each reviewer's search-protocol discriminations between these nodules and ambiguous normal findings. This superiority-of-search result suggests that radiologists' second opinions about suspected lesions might be more accurate when consultants follow a search protocol, independently reviewing radiographs without prior knowledge of the specific findings that concerned the primary radiograph readers.