Figure and Table | Short-term All-cause In-hospital Mortality Prediction by Machine Learning Using Numeric Laboratory Results

Table 1. Critical Value List (Numeric Range Only).

Category	Test item	Critical value
Chemistry	Glucose	≦50 or ≧450 mg/dL
	Creatinine	≧3 mg/dL
	Total bilirubin	≧5 mg/dL
	Alkaline phosphatase	≧1000 IU/L
	Lactate dehydrogenase	≧1000 IU/L
	Aspartate aminotransferase	≧1000 IU/L
	Alanine aminotransferase	≧1000 IU/L
	Amylase	≧1000 IU/L
	Creatine kinase	≧5000 IU/L
	Calcium	≦6 or ≧12 mg/dl
	Sodium	≦119 or ≧160 mmol/L
	Potassium	≦2.5 or ≧6 mmol/L
Hematology	White blood cell count	≦2 or ≧20 × 10³/mm³
	Hemoglobin	≦8 or ≧17 g/dL
	Platelet count	≦50 or ≧700 × 10³/mm³
	Neutrophil count	≦0.5 × 10³/mm³
	Lymphocyte rate	≧70%
	Atypical lymphocyte rate	≧10%
	Eosinocyte rate	≧20%
Coagulation	PT-INR	≧4
	Activated partial thromboplastin time	≧225 seconds
	Fibrinogen	≦100 mg/dL

Table 2. Cohort Characteristics.

	Model data	External Validation data
Period	12 months	6 months
Number of patients	51240	35480
Gender
Male	21031	15118
Female	30209	20362
Age at laboratory tests (mean ± SD)	59.0 ± 18.5	59.1 ± 18.5

Number of laboratory tests	223422	112008
Number of laboratory test items	7691243	3889926

Number of laboratory tests by patient location
Outpatient	169743	84773
General ward	42089	21793
Intensive care unit	10944	5155
Palliative care unit	646	287

Number of laboratory tests by requesting department
Obstetrics and gynecology	36946	18105
Immuno-Rheumatology	22013	11000
Cardiology	20785	10208
Nephrology	15464	8158
Emergency room	12044	6181
Urology	11815	5731
Endocrinology	11772	6002
Gastroenterology	11509	5999
Hematology	10493	5036
Anesthesiology	10110	5012
Oncology	10004	5188
Respiratory medicine	9351	4795
Internal medicine	9177	4569
Breast surgery	8480	3680
General surgery	6167	3157
Infectious disease	5821	2651
Cardiovascular surgery	4518	2668
Orthopedics	4423	2310
Dermatology	3345	1685
Neurosurgery	3114	1814
Neurology	2313	1041
Psychiatry	1329	729
Thoracic surgery	1324	765
Ophthalmology	1158	566
Plastic surgery	942	499
Neurovascular	774	275
Palliative care	693	312
Otorhinolaryngology	686	412
Oral surgery	212	123
Radiology	156	43
Others	373	264

Number of laboratory tests with critical values	20297	9948
Number of deceased patients	522	260
Number of laboratory tests conducted within 7 days of death	1334 (0.6%)	589 (0.5%)

Table 3. Cross-Validation Result.

Validation	Accuracy	ROC-AUC	Recall	Precision	F1
1	0.9197	0.9757	0.9355	0.0651	0.1217
2	0.9222	0.9839	0.9787	0.0704	0.1313
3	0.9113	0.9688	0.9255	0.0593	0.1114
4	0.9133	0.9838	0.9681	0.0630	0.1183
5	0.9072	0.9750	0.9255	0.0568	0.1071
6	0.9112	0.9811	0.9785	0.0616	0.1158
7	0.9195	0.9849	0.9785	0.0675	0.1263
8	0.9261	0.9868	0.9785	0.0732	0.1361
9	0.9190	0.9793	0.9462	0.0652	0.1220
10	0.9134	0.9768	0.9247	0.0600	0.1127
Mean ± SD	0.9163 ± 0.0056	0.9796 ± 0.0053	0.9540 ± 0.0234	0.0642 ± 0.0049	0.1203 ± 0.0087

Table 4. Summary and Prediction Results from 30% Model Data and Validation Data.

	30% of Model data		Validation data
Number of patients	29258		35480
Number of deceased patients	270		260
Number of laboratory tests	67027		112008
Number of negative laboratory tests	66627		111419
	Correct	Incorrect	Correct	Incorrect
CVL prediction	60785	5842	101754	9665
XGB prediction	61153	5474	105496	5923
Number of positive laboratory tests	400		589
	Correct	Incorrect	Correct	Incorrect
CVL prediction	239	161	307	282
XGB prediction	382	18	460	129

Table 5. Comparison of Prediction Results from 30% Model Data and External Validation Data.