Table 2.

Uplift model performance in a test set of patients in a randomized trial of AKI alerts

Uplift Model	Association with ΔCr3 (% per SD)	P Value	ΔCr3 Difference (Alert versus Control), (% per SD)	Interaction P Value
T-Learner, alert	1.5 (−1.5 to 4.5)	0.32	−5.8 (−10.8 to −0.8)	0.02
T-Learner, usual care	7.3 (0.32–11.4)	0.001
Z-Learner, alert	1.2 (−1.7 to 4.2)	0.41	−6.5 (−11.5 to −1.4)	0.01
Z-Learner, usual care	7.7 (3.5–11.9)	<0.001
X-Learner, alert	1.6 (−1.4 to 4.6)	0.29	−5.8 (−10.8 to −0.7)	0.03
X-Learner, usual care	7.4 (3.3–11.5)	<0.001
Prognostic, alert	3.0 (0.1–5.9)	0.04	−2.5 (−7.2 to 2.2)	0.30
Prognostic, usual care	5.5 (1.7–9.3)	0.004

Performance of various uplift models and the prognostic model. Association between uplift scores and change in creatinine per one SD increase in model score shows that increases in all models are associated with worse overall outcomes in terms of ΔCr₃ in the usual care arm. Difference in change in creatinine between alert and control groups demonstrate the increased efficacy of alerting as uplift scores increase (negative numbers indicate alerting is associated with improved ΔCr₃). ΔCr₃, maximum relative change in creatinine from time of randomization to 3 days postrandomization.