Statistical analysis
We calculated the test characteristics of the electronic sepsis alert system, including the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood the ratio with corresponding 95% confidence intervals (CIs). For patients’ who were referred to ICU, we collected additional demographic and clinical data. In addition, we calculated the time from alert activation to the ICU referral and values were expressed as medians and quartiles. We used the SPSS 20.0 software package (SPSS Inc., Chicago, IL, USA) for statistical analysis.