Interobserver variability in interpretation of coronary arteriograms
Several recent studies suggest that there may be more interobserver and intraobserver variability in the interpretation of coronary arteriograms than had been previously thought to exist.1–3 Because of these data, a study was initiated utilizing data from the Coronary Artery Surgical Study supported by the National Heart, Lung and Blood Institute. This is a multicenter study of the effect of coronary artery bypass surgery on the natural history of coronary artery disease. The centers participating have entered the interpretation of coronary arteriography on consecutive patients studied into a data bank at the Coordinating Center at the University of Washington in Seattle. Three of the centers have served as quality control centers reinterpreting an aliquot of films from each of the other centers. These data form the basis of this report.
A pilot study was performed by the three quality control centers. Thirty films were chosen by the Coordinating Center excluding films that were considered to be normal. These 30 films were divided into groups of ten films and were sent to each quality control site for a consensus interpretation. The films were then exchanged until each site had read each group of ten; and then the process was repeated for a second round of interpretation of the same films. In this manner, both interobserver and intraobserver variability could be assessed.
We initially studied agreement on the number of vessels involved. A vessel was considered significantly stenosed if it contained a lesion of 70% or greater in any major coronary . . .