Year of publication |
|
2017 |
2017 |
2017 |
2019 |
2019 |
Sample size |
Development cohort |
573 |
2,123 |
1,084 |
4,572 |
19,160 |
Internal validation cohort |
144 |
2,123 |
1,084 |
1,958 |
4,790 |
External validation cohort |
1,300 |
2,367 (independent split set of the original data) |
Not applicable |
Not applicable |
Not applicable |
Study type |
Prospective or retrospective |
Prospective |
Retrospective |
Prospective |
Retrospective |
Retrospective |
Single-center or multicenter |
Multicenter |
Multicenter |
Multicenter |
Single-center |
Single-center |
Patient population |
|
Adult patients admitted to ICU without known AKI at enrollment |
Adult patients admitted to ICU without a history of ESRD and a baseline SCr ≥ 4mg/dL |
Adult patients admitted to ICU |
Adult patients admitted to ICU without ESRD and history of AKI |
Adult patients admitted to ICU without CKD and AKI on admission |
AKI definition |
Criteria |
KDIGO SCr criteria |
KDIGO SCr criteria |
KDIGO SCr and/or UO criteria |
AKIN SCr and/or UO criteria |
KDIGO SCr criteria |
Baseline SCr |
SCr measurements 7 to 365 days before ICU admission |
SCr measurements 1 week to 3 months before |
SCr measurements 3 to > 365 days before ICU admission |
SCr measurements 180 days before ICU admission |
Day1 minimum SCr |
Imputed baseline SCr |
SCr at ICU admission |
MDRD back calculation |
SCr at ICU admission, or follow-up up to 365 days |
MDRD back calculation |
Not applicable since no patients lacked baseline SCr |
Incidence of outcome (%) |
Development cohort |
22 |
27.7 |
30.1 |
30 |
16.5 |
Internal validation cohort |
24 |
27.7 |
30.1 |
30 |
16.5 |
External validation cohort |
45 |
29.2 (independent split set of the original data) |
Not applicable |
Not applicable |
Not applicable |
Missing preadmission SCr values (%) |
Development cohort |
24 |
22.8 |
36.0 |
Not reported |
Not reported |
Internal validation cohort |
24 |
22.8 |
36.0 |
Not reported |
Not reported |
External validation cohort |
30 |
22.9 (independent split set of the original data) |
Not applicable |
Not applicable |
Not applicable |
Timeframe |
Collection of risk predictors |
Within 48 hours after ICU admission |
Within 1 day after ICU admission |
Within 1 day after ICU admission |
Up to 1 day before the time of prediction |
Within 1 day after ICU admission |
Prediction |
Within 1 week after study enrollment |
Within 1 week after ICU admission |
Within 1 week after ICU enrollment |
Every 15 minutes after ICU admission |
Within 72 hours after ICU admission |
Number of risk factors for any AKI |
|
10 |
12 |
5 |
19 |
16 |
Techniques |
Variable selection |
Stepwise forward elimination |
Backward elimination method |
Stepwise method |
Stepwise regression algorithm |
Backward elimination method |
Modeling algorithm |
MLR |
Random forest |
ULR and MLR |
Random forest |
MLR |
Internal validation |
5-fold cross-validation |
Bootstrapping |
Bootstrapping |
Random split |
5-fold cross-validation |
External validation |
Independent prospective cohort |
Independent split set of the original data |
Not applicable |
Not applicable |
Not applicable |
Discrimination (AUROC) |
Development cohort |
Not reported |
0.86 (0.86 - 0.86) |
0.821 (0.792 - 0.850) |
0.949 (0.943 - 0.954) |
Not reported |
Internal validation cohort |
0.792 (0.697 - 0.887) |
0.86 (0.86 - 0.86) |
0.821 (0.792 - 0.850) |
0.882 (0.867 - 0.897) |
0.78 |
External validation cohort |
0.81 (0.78 - 0.83) |
0.81 (0.81 - 0.81) |
Not applicable |
Not applicable |
Not applicable |
Calibration |
Development cohort |
Not reported |
Calibration slope: 0.87 (0.87 - 0.88), |
Not applicable |
H-L test p-value: |
Not applicable |
Calibration in the large: -0.00, and calibration curve |
0.3, and calibration curve |
Internal validation cohort |
Hosmer-Lemeshow test p-value: 0.293, and calibration curve |
Calibration slope: 0.87 (0.87 - 0.88), |
Not applicable |
Hosmer-Lemeshow test p-value: 0.3, and calibration curve |
Not applicable |
calibration in the large: -0.00 (-0.01 - 0.00), and calibration curve |
External validation cohort |
Calibration curve |
Calibration slope: 0.78 (0.78 - 0.79), calibration in the large: -0.01 (-0.01 – -0.01), and calibration curve |
Not applicable |
Not applicable |
Not applicable |