Data source
All the patient data used in our study came from an online international database—Medical Information Mart for Intensive Care III (MIMIC III) (version 1.4). MIMIC III is a large, single-center database comprising information related to patients admitted to critical care units of Beth Israel Deaconess Medical Center. It included patients who were admitted to the ICU between 2001 and 2012. This database includes a total of 53,423 different admission data points. MIMIC III contains a wealth of clinical information, including vital signs, demographic information, laboratory results, treatment records and nursing records. The Institutional Review Boards at both Massachusetts Institute of Technology and the Beth Israel Deaconess Medical Center approved the use of the data for research. The database can be accessed by certified researchers, so no additional informed consent of the patient and ethical approval are required [