The principles and guidelines at our center

are driven by the potential benefit of the SPK transplant needing to outweigh the increased morbidity of the surgical procedure and the use of lifelong immunosuppression. Results from long-term studies demonstrating improved patient survival suggest that the treatment of choice for an appropriate type 1 diabetic recipient is an SPK transplant.”
“Background: Statistical process control (SPC), an industrial sphere initiative, has recently been applied in health care and public health surveillance. SPC methods assume HDAC inhibitor independent observations and process autocorrelation has been associated with increase in false alarm frequency.

Methods: Monthly mean raw mortality (at hospital discharge) time series, 1995-2009, at the individual Intensive Care unit (ICU) level, were generated from the Australia and New Zealand Intensive Care Society adult patient database. Evidence for series (i) autocorrelation and seasonality was demonstrated using

(partial)-autocorrelation ((P) ACF) function displays and classical series decomposition and (ii) “”in-control”" status was sought using risk-adjusted (RA) exponentially weighted moving average (EWMA) control limits (3 sigma). Risk adjustment was achieved using a random coefficient (intercept as ICU site and slope as APACHE III score) logistic regression model, generating an expected mortality series. Application of time-series to an exemplar complete ICU series (1995-(end) www.selleckchem.com/products/ly333531.html 2009) was via Box-Jenkins methodology: autoregressive selleck chemicals llc moving average (ARMA) and (G) ARCH ((Generalised) Autoregressive Conditional Heteroscedasticity) models, the latter addressing volatility of the series variance.

Results: The overall data set, 1995-2009, consisted

of 491324 records from 137 ICU sites; average raw mortality was 14.07%; average(SD) raw and expected mortalities ranged from 0.012(0.113) and 0.013(0.045) to 0.296(0.457) and 0.278 (0.247) respectively. For the raw mortality series: 71 sites had continuous data for assessment up to or beyond lag(40) and 35% had autocorrelation through to lag40; and of 36 sites with continuous data for >= 72 months, all demonstrated marked seasonality. Similar numbers and percentages were seen with the expected series. Out-of-control signalling was evident for the raw mortality series with respect to RA-EWMA control limits; a seasonal ARMA model, with GARCH effects, displayed white-noise residuals which were in-control with respect to EWMA control limits and one-step prediction error limits (3SE). The expected series was modelled with a multiplicative seasonal autoregressive model.

Conclusions: The data generating process of monthly raw mortality series at the ICU level displayed autocorrelation, seasonality and volatility. False-positive signalling of the raw mortality series was evident with respect to RA-EWMA control limits.