2.1. Data source
In this study, we used the Medical Information Mart for Intensive Care III (MIMIC-III) 2001-2012 [14] for the data extraction and model development. There were 53,423patients with different diseases and the database was included in the vital signs, drugs and laboratory measurement, observation and care providers of record, liquid balance, program code, diagnosis, imaging report, length of hospital stays, survival data, etc. MIMIC-III included almost comprehensive clinical data of patients admitted to the Beth Israel Deaconess Medical Center in Boston, Massachusetts.