Extended Data Table 4 |. Operating points for predicting AKI up to 48 hours ahead of time.

(a) For prediction of any AKI, the model correctly identifies 55.8% of all AKI episodes early if allowing for two false positives for every true positive, and 34.7% if allowing for one false positive for every true positive. For more severe AKI stages it is possible to achieve a higher sensitivity for any fixed level of precision. Performance increases for prediction of (b) AKI stages 2 & 3, and (c) AKI stage 3 alone. 95% bootstrap pivot confidence intervals are calculated using n=200 bootstrap samples for all tables.

a
Operating points for predicting any AKI up to 48 hours ahead of time
Precision	True positive / False positive	Sensitivity [95% Cl] (AKI episode)	Sensitivity [95% Cl] (step)	Specificity [95% Cl] (step)
20.0%	1:4	76.7% [75.6, 77.8]	58.3% [56.9, 59.8]	94.8% [94.6, 95.1]
25.0%	1:3	68.2% [66.9, 69.7]	47.7% [46.1,49.4]	96.8% [96.6, 97.0]
33.0%	1:2	55.8% [53.9, 57.7]	35.0% [33.3, 36.7]	98.4% [98.3, 98.5]
40.0%	2:3	46.6% [44.5, 49.0]	27.1% [25.2, 28.9]	99.1% [99.0, 99.2]
50.0%	1:1	34.7% [32.0, 37.2]	18.5% [16.7, 20.3]	99.6% [99.5, 99.6]
60.0%	3:2	24.7% [21.8, 27.3]	12.4% [10.5, 13.9]	99.8% [99.8, 99.8]
75.0%	3:1	12.0% [9.3, 14.6]	5.5% [3.9, 7.0]	100.0% [99.9, 100.0]
b
Operating points for predicting AKI stages 2 and 3 up to 48 hours ahead of time
Precision	True positive / False positive	Sensitivity [95% Cl] (AKI episode)	Sensitivity [95% Cl] (step)	Specificity [95% Cl] (step)
20.0%	1:4	82.0% [80.6, 83.5]	65.8% [64.0, 67.9]	98.5% [98.4, 98.6]
25.0%	1:3	77.8% [76.3, 79.7]	60.4% [58.3, 62.8]	99.0% [98.9, 99.1]
33.0%	1:2	71.4% [69.6, 73.7]	51.8% [49.6, 54.8]	99.4% [99.4, 99.5]
40.0%	2:3	65.2% [63.0, 67.7]	44.6% [42.1,47.3]	99.6% [99.6, 99.7]
50.0%	1:1	56.2% [54.0, 59.2]	35.8% [33.5, 38.9]	99.8% [99.8, 99.8]
60.0%	3:2	45.1% [42.2, 48.6]	26.3% [23.8, 29.4]	99.9% [99.9, 99.9]
75.0%	3:1	27.5% [24.2, 31.5]	13.8% [11.7, 16.3]	100.0% [100.0, 100.0]
c
Operating points for predicting AKI stage 3 up to 48 hours ahead of time
Precision	True positive / False positive	Sensitivity [95% Cl] (AKI episode)	Sensitivity [95% Cl] (step)	Specificity [95% Cl] (step)
20.0%	1:4	91.2% [90.4, 92.3]	80.3% [78.4, 82.4]	98.8% [98.7, 98.9]
25.0%	1:3	88.8% [87.7, 90.1]	75.8% [73.7, 78.3]	99.1% [99.0, 99.2]
33.0%	1:2	84.1% [82.4, 85.9]	68.3% [65.7, 71.0]	99.5% [99.4, 99.5]
40.0%	2:3	79.5% [77.4, 81.8]	61.1% [57.9, 64.5]	99.7% [99.6, 99.7]
50.0%	1:1	71.3% [68.3, 74.4]	50.2% [46.4, 53.8]	99.8% [99.8, 99.8]
60.0%	3:2	61.2% [57.6, 64.9]	39.9% [35.7, 43.8]	99.9% [99.9, 99.9]
75.0%	3:1	40.5% [36.5, 46.1]	23.2% [19.6, 27.2]	100.0% [100.0, 100.0]