EWMA control charts for monitoring binary processes with applications to medical diagnosis data

To monitor a binary process, exponentially weighted moving average (EWMA) control charts in different variations are proposed. The average run length performance of the EWMA approach both with standard and with skewness-corrected 3-σ control limits is investigated and design recommendations are derived. The proposed EWMA control charts are applied to medical diagnosis data taken from the diagnostic expert system SONOCONSULT in order to provide a semi-automatic component for monitoring the documentation behavior of different examiners. Copyright © 2010 John Wiley & Sons, Ltd.