Stefan H. Steiner

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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(More)
One strategy to reduce the consumption of resources associated to specific procedures is to utilize clinical pathways, in which surgical care is standardized and preset by determination of perioperative in-hospital processes. The aim of this prospective study was to establish the impact of clinical pathways on costs, complication rates, and nursing(More)
Correlated binary data are encountered in many areas of medical research, system reliability and quality control. For monitoring failures rates in such situations, simultaneous bivariate cumulative sum (CUSUM) charts with the addition of secondary control limits are proposed. Using an approach based on a Markov chain model, the run length properties of such(More)
The control limits of an exponentially weighted moving average (EWMA) control chart should vary with time, approaching asymptotic limits as time increases. However, previous analytic analyses of EWMA charts consider only asymptotic control limits. In this article, the run length properties of EWMAs with time-varying control limits are approximated using(More)
Mark A. Jones, Stefan H. Steiner. Assessing the effect of estimation error on risk-adjusted CUSUM chart performance. Int J Qual Health Care (2012) 24(2): 176–181 doi: 10.1093/intqhc/mzr082. The authors would like to correct an error identified in the above paper. Table 5 included incorrect information. The correct table has been reprinted below.(More)
Monitoring medical outcomes is desirable to help quickly detect performance changes. Previous applications have focused mostly on binary outcomes, such as 30-day mortality after surgery. However, in many applications the survival time data are routinely collected. In this paper, we propose an updating exponentially weighted moving average (EWMA) control(More)
Inappropriate sinus tachycardia is a disease which is relatively rarely found and sometimes difficult to treat. Up to now it has been mostly treated with a beta-blocker or verapamil. If this did not work sinus node modulation was considered. Since the relatively new selective IF-stream blocker ivabradine has been approved for the therapy of chronic stable(More)
A graphical procedure suitable for prospectively monitoring surgical performance is proposed. The approach is based on accumulating evidence from the outcomes of all previous surgical patients in a series using a new type of cumulative sum chart. Cumulative sum procedures are designed to "signal" if sufficient evidence has accumulated that the surgical(More)
OBJECTIVE To present graphical procedures for prospectively monitoring outcomes in the intensive care unit. DESIGN Observational study: risk-adjusted control chart analysis of a case series. SETTING Tertiary referral adult intensive care unit: Princess Alexandra Hospital, Brisbane, Australia. PATIENTS A total of 3398 intensive care unit admissions(More)