During the past four years, a large number of radiographic images have been interpreted in both film and video modes in an effort to determine the utility of digital/analogue systems in general practice. With the cooperation of the Department of Defense, the MITRE Corporation, and several university-based radiology departments, the Public Health Service has participated in laboratory experiments and a teleradiology field trial to meet this objective. During the field trial, 30 radiologists participated in the interpretation of more than 4,000 diagnostic x-ray examinations that were performed at distant clinics, digitized, and transmitted to a medical center for interpretation on video monitors. As part of the evaluation, all of the participating radiologists and the attending physicians at the clinics were queried regarding the teleradiology system, particularly with respect to the diagnostic quality of the electronic images. The original films for each of the 4,000 examinations were read independently, and the findings and impressions from each mode were compared to identify discrepancies. In addition, a sample of 530 cases was reviewed and interpreted by a consensus panel to measure the accuracy of findings and impressions of both film and video readings. The sample has been retained in an automated archive for future study at the National Center of Devices and Radiological Health facilities in Rockville, Maryland. The studies include a comparison of diagnostic findings and impressions from 1024 x 1024 matrices with those obtained from the 512 x 512 format used in the field trial. The archive also provides a database for determining the effect of data compression techniques on diagnostic interpretations and establishing the utility of image processing algorithms. The paper will include an analysis of the final results of the field trial and preliminary findings from the ongoing studies using the archive of cases at the National Center for Devices and Radiological Health. This paper was not available at the time of printing of the Proceedings.