Reader Study of DeltaView™ Chest Radiograph Software

Completed

Brief Summary: A new software product takes two chest radiographs, aligns them, and then subtracts one image from the other. The resulting image represents an image showing any differences between them. The study is to determine whether radiologists using this new software perform better with it than when they do not use it.

Recruitment & Eligibility

Inclusion Criteria

For Radiologists: American Board of Radiology Certification and live within the Baltimore, MD-Washington, DC Metropolitan areas

For chest radiographs, evidence of the presence or absence of lung nodule confirmed by expert panel; adequate image quality

Exclusion Criteria

Radiologists who assisted by providing cases for review

For chest radiographs: poor image quality

Primary Outcome Measures

Name	Time	Method
Localized Receiver Operating Characteristic (LROC) Comparison	1 day	The area under the LROC curve will be compared for the chest radiograph interpretations done without the new software and those done with the new software. Improvement will be demonstrated if the improvement with the new software is statistically significant at the p=\<0.05. There were 422 cases in the total study. 20 of these were inserted as "noise" cases, not to be analyzed. Thus there were 402 cases to be analyzed. There were 120 cases with nodules and 282 without a nodule. LROC is a method for measuring the success or failure of a method where there is a tradeoff between the detection of lung nodules that are there (true positives) and the detection that the radiologist considers to be a nodule where no nodule is present (false positive). It yields a single number that done not have a unit of measurement.

Secondary Outcome Measures

Name	Time	Method
False Positive Decisions of Radiologists	1 day	This is a comparison of the radiologists working without and with the software. The false positive rate is the percentage of cases in which the radiologists identified a lesions/location suspected of being cancer at a location where cancer was not present. . A false positive represents a location selected on a chest image without cancer and, also, a mark on a chest image where cancer was present, but a different location, one without cancer, was marked.The radiologists could mark up to five locations on an image and had to provide a confidence rating for each. This analysis is of the single mark with the highest confidence level.
Sensitivity and Specificity	1 day	Sensitivity and specificity will be measured. If the radiologists using the new software have higher sensitivity, statistically significant at the p=\< 0.05, the use of the new software will be considered to have resulted in improvement. A decrease in specificity is expected.