Detection or decision errors? Missed lung cancer from the posteroanterior chest radiograph.

A test bank of verified chest radiographs was compiled for visual search experiments to investigate radiology performance in the detection of early lung cancer. A measure of the physical characteristics of the lesions was derived to determine the conspicuity (chi) of the nodules and to investigate possible causes of failed detection. Observer performance was measured by alternate free response operating characteristic (AFROC) methodology and was supplemented with visual search recording. Correlation of AFROC scores and the chi values was poor but inspection of the visual search recordings showed that most nodules were fixated. Fixations on missed lesions produced average dwell times greater than three times the minimum duration thought to be associated with detection. We conclude that the majority of errors were failures of decision rather than detection and comment on the implications of this for strategies to improve diagnostic effectiveness.

Accident and emergency and general practitioner plain radiograph reporting by radiographers and radiologists: a quasi-randomized controlled trial.

Two specially trained radiographers at York District Hospital have been reporting appendicular plain radiograph X-ray examinations for Accident and Emergency (A&E) patients since February 1995. This study explores the potential for further expanding their reporting role. This was achieved by assessing the two radiographers' and a group of consultant radiologists' ability to report on a retrospectively selected random stratified sample of 400 A&E and General Practitioner (GP) plain radiograph X-ray examinations for all body areas. Using receiver operating characteristic (ROC) curve analyses there was no statistically significant difference at the 5% level between the area under the ROC curves for the radiographers and consultant radiologists when reporting A&E or GP plain radiographs. It may be feasible to expand the reporting role of suitably trained radiographers to include plain radiograph X-ray examinations for all A&E patients and for GP patients, with no detriment to the quality of reports.