Usually, in monitoring schemes the nominal value of the process parameter is assumed known. However, this assumption is violated owing to costly sampling and lack of data particularly in healthcare systems. On the other hand, applying a fixed control limit for the risk-adjusted Bernoulli chart causes to a variable in-control average run length performance for patient populations with dissimilar...

Attribute control charts (e.g., charts for counts and proportions) have discrete jumps in the quantities plotted on the charts, which means that the chart designer has only a discrete set of unique control limits to choose from when designing a chart. These charts have a small set of in-control Average Run Lengths (ARLs) from which to determine the appropriate control scheme. In a chart with ra...

For an improved monitoring of process parameters, it is generally desirable to have ef?cient designs of control charting structures. The addition of Shewhart control limits to the cumulative sum (CUSUM) control chart is a simple monitoring scheme sensitive to wide range of mean shifts. To improve the detection ability of the combined Shewhart–CUSUM control chart to off-target processes, we deve...

results total prevalence's of subjects with wrist-hand, shoulder-arm, neck back and lower limb disorders were obtained 556 (82.6%), 352 (52.3%), 238 (35.4%), 454 (67.5%), and 149 (22.1%) respectively (p = 0.028). the highest cumulative risk was corresponded to wrist-hand, and after that were cumulative risks of back, shoulder-arm, neck, and lower limb respectively. objectives this study was con...

The cumulative sum (CUSUM) procedure is a graphical method that is widely used for quality monitoring in industrial settings. More recently it has been used to monitor surgical outcomes whereby it 'signals' if sufficient evidence has accumulated that there has been a change in the surgical failure rate. A limitation of the standard CUSUM procedure in this context is that since it is simply base...

BACKGROUND Time series charts are increasingly used by clinical teams to monitor their performance, but statistical control charts are not widely used, partly due to uncertainty about which chart to use. Although there is a large literature on methods, there are few systematic comparisons of charts for detecting changes in rates of binary clinical performance data. METHODS We compared four co...

The aim of this study was to detect arising weak points in pig breeding early for starting counteractive measures. Control-Charts are an instrument for monitoring industrial manufacturing processes and for statistical quality management. Two kinds of these charts were analysed in this study, first the Exponentially Weighted Moving Average (EWMA)-Charts, and on the other hand the Cumulative Sum ...