Fig 1.
Blood samplings required for the standard 4-hour and 8-hour one-compartment models (Panels C and B), for the reference 10-hour two-compartment model (Panel A), and the simplified two-compartment popPK model (Panel D).
Table 1.
Baseline characteristics and kidney function parameters of study participants included in Phase A and Phase B.
Fig 2.
Mountain plot analysis showing a percentile for each ranked difference between the standard 10-hour two-compartment model (reference GFR) and the simplified two-compartment popPK model (popPK GFR), MDRD (MDRD eGFR) and CKD-Epi (CKD-Epi eGFR) in the study group considered as a whole (Panel A, Overall, n = 40) and only first, baseline clearance studies available from each individual patient (Panel B, Baseline Analyses, n = 16).
Fig 3.
Bland–Altman plots obtained with popPK model and the standard 10-hour two-compartment model.
Bland–Altman plots and limits of agreement between GFR obtained with the simplified two-compartment popPK model (popPK GFR) and the standard 10-hour two-compartment model (reference-GFR) in the study group considered as a whole (Panel A, Overall, n = 40) and only first, baseline clearance studies available from each individual patient (Panel B, Baseline Analyses, n = 16).
Fig 4.
Intercept random model for Phase A.
Intercept random model based on standard 10-hour two-compartment model (reference GFR) versus the simplified two-compartment popPK model (popPK GFR), MDRD (MDRD eGFR) and CKD-Epi (CKD-Epi eGFR) (n = 40).
Table 2.
Agreement of the Performance of the simplified two-compartment popPK model, CKD-Epi and MDRD versus the standard 10 hour two compartment model in 40 clearance studies performed in 16 patients considered as a whole (Overall).
Fig 5.
Bland–Altman plots with 8-hour vs. 7, 6 and 5 hours after iohexol infusion.
Bland–Altman plots and limits of agreement between GFR values obtained with the one-compartment models shortened to 7, 6, or 5 hours versus the GFR values obtained with the standard 8-hour procedure. Upper panels show data obtained from all available clearance measurements (Overall); Lower panels show data obtained from the first, baseline, clearance measurements available from each individual patient (Baseline Analyses).
Fig 6.
GFRs measured with 8-hour vs. 7, 6 and 5 hours after iohexol infusion.
GFR values measured with the 8-hour standard one-compartment model versus GFR values obtained with shortened one-compartment protocols stopped at 7, 6 and 5-hours after iohexol infusion considering all available clearance studies (Panel A, Overall, n = 216) and only first, baseline clearance studies available from each individual patient (Panel B, Baseline Analyses, n = 101). Data are mean ± 95% confidence intervals.
Fig 7.
Mountain plot with 8-hour vs. 7, 6 and 5 hours after iohexol infusion.
Mountain plot analysis showing a percentile for each ranked difference between the standard 8-hour one-compartment model (8-hour GFR) and different shortened protocols (7, 6 and 5-hours GFR) and Plot analysis was performed by using GFR data obtained from all available clearance measurements (Panel A, Overall, n = 216) and only from the first, baseline, clearance measurement available from each individual patient (Panel B, Baseline Analyses, n = 101).
Fig 8.
Intercept random model for Phase B.
Intercept random model based on GFR values measured with the 8-hour standard one-compartment model versus GFR values obtained with 7, 6 and 5-hours models and CKD-Epi and MDRD formulas (n = 216).
Table 3.
Performance of shortened 7-, 6- and 5-hour one compartment models and of CKD-Epi and MDRD equations versus the standard 8-hour one-compartment model in 216 clearance studies performed in 101 patients with e GFR <40 ml/min/1.73 m2.