Table 2. Top variables selected by machine learning procedure that increase risk of readmission within 30 days.

Top supportive evidence
Variable class	Variable description	Log Odds Ratio	Log Odds Ratio Standard Error1
Lab Results	Lymphocyte % is low	0.0128	0.0027
Patterns of Engagement	Patient was admitted in past 6 months	0.0112	0.0031
Lab Results	BUN is high	0.0038	0.0012
Lab Results	Glucose level random is elevated	0.003	0.0012
Lab Results	Monocyte absolute is low	0.0028	0.0012
Other Diagnoses	History of nondependent abuse of drugs (ICD9 305.x)	0.0018	0.001
Other Diagnoses	History of chronic airway obstruction, not elsewhere classified (ICD9 496.x)	0.0017	0.0008
Other Diagnoses	History of gastrointestinal hemorrhage (ICD9 578.x)	0.0014	0.0007
Lab Results	AST is elevated	0.0013	0.0006
Other Diagnoses	History of cardiomyopathy (ICD9 425.x)	0.001	0.0006
Lab Results	Magnesium is low	0.001	0.0006
Lab Results	INR is elevated	0.0009	0.0004
Patterns of Engagement	Patient has been in isolated room in hospital	0.0009	0.0006
Lab Results	BNP is high	0.0007	0.0005

These are variables that receive positive log-odds ratio with the largest magnitude.

1. Obtained from sample standard error for cross-validation odds ratios