Clinical diagnosis from digital displays: results and conclusions from the St Mary's evaluation project.

Preliminary results with the first commercially available digital display system to be installed in a British radiology department were published in 1989: these consisted of data from observer performance studies of digitized images displayed using a 1024-line monitor, showing a single pathological feature--subperiosteal resorption in renal osteodystrophy. Further experiments have now been conducted with the successor to this equipment, a 1280-line digital display system. Formal observer performance studies were undertaken for four pathological conditions, and the results show statistically significant differences in performance between the digitized displayed images and those on film. The display system was not considered to be good enough for the task of primary radiological diagnosis of subtle lesions; findings support the conclusion that careful, objective clinical evaluation of digital display systems is important before they are introduced into clinical use.

Clinical diagnosis from digital displays: preliminary findings of the St Mary's Evaluation Project.

Image quality is a fundamental issue in the introduction of picture archiving and communications systems (PACS), and one that has hitherto been eclipsed by other aspects of the considerable technological challenge facing scientists and manufacturers involved in its development. We conducted a formal evaluation of clinical radiological diagnosis from a commercially available PACS viewing station, using subperiosteal resorbtion in renal osteodystrophy as the test pathological diagnosis, with receiver operating characteristic (ROC) analysis of the results. We conclude that the displayed, digitised images were inferior to film using the apparatus tested and believe that careful, objective clinical evaluation of such systems is of paramount important.

The incidence of childhood diabetes in certain parts of Scotland.

The incidence of diabetes in children under 12 years of age has been studied in three regions of Scotland from 1976 to 1986. These areas represent more than half of the Scottish population of that age group. The overall annual incidence is 17.6 per 100,000, ranging from 16.8 in densely populated areas to 23.4 in more rural areas. Earlier studies have concerned the age group 0-18 years so the present results from a younger age group are, as expected, slightly lower but show the same trends. After a rise to 1983 there appears to have been a drop, but not in all areas. The danger of drawing conclusions from areas of low population or from short periods of time is stressed.