Table 2.

Performance of the two-stage model and each individual model stage, in 95% confidence intervals.

	Two-stage model		Stage 1 (regexes)		Stage 2 (LASSO)
Cohort	RMSE [95% CI]	SC [95% CI]	RMSE [95% CI]	SC [95% CI]	RMSE [95% CI]	SC [95% CI]
MGH hold-out test set	3.13 [2.86, 3.41]	0.90 [0.88, 0.91]	1.93 [1.49, 2.39]	0.95 [0.93, 0.97]	3.72 [3.38, 4.10]	0.87 [0.86, 0.89]
MIMIC validation set	2.01 [1.58, 2.38]	0.96 [0.94, 0.97]	0.61 [0.00, 1.01]	1.00 [0.99, 1.00]	4.00 [3.32, 4.70]	0.81 [0.71, 0.89]

MIMIC – Medical Information Mart for Intensive Care-MIMIC III; CI – confidence intervals; MGH – Massachusetts General Hospital; Regexes – regular expressions; RMSE – root mean squared error; SC – Spearman correlation.