Table 8.

The mean area under the receiver operating characteristic curve (ROC AUC) scores for each individual feature class, and combined classifier measured using 5-fold cross validation.

Classifier	Logistic regression	K-nearest neighbors	Random forest
Age	0.689	0.620	0.697
Body mass index	0.572	0.530	0.575
Service	0.693	0.635	0.693
Surgery	0.619	0.602	0.630
Medication (single)	0.600	0.554	0.619
Medication class	0.606	0.584	0.625
Medication hierarchy	0.608	0.579	0.622
Inpatient ICD-9-CM chapter	0.801	0.748	0.815
Inpatient ICD-9-CM PHEWAS	0.769	0.720	0.791
Inpatient ICD-9-CM parent	0.749	0.715	0.783
Inpatient ICD-9-CM code	0.715	0.704	0.769
Inpatient ICD-9-CM hierarchy	0.820	0.785	0.859
Temporal inpatient ICD-9-CM	0.800	0.754	0.817
Outpatient ICD-9-CM chapter	0.774	0.718	0.794
Outpatient ICD-9-CM PHEWAS	0.760	0.689	0.774
Outpatient ICD-9-CM parent	0.740	0.667	0.769
Outpatient ICD-9-CM code	0.689	0.627	0.728
Outpatient ICD-9-CM hierarchy	0.800	0.774	0.856
Temporal outpatient ICD-9-CM	0.791	0.753	0.815

ICD-9-CM = International classification of diseases and related health problems, ninth revision, clinical modification