Table 2.

A clinical score to stratify risk of postnephrectomy eGFR <45 ml/min per 1.73 m²

Variable	Coefficient	Points	Score	Risk Stratum	Predicted Probabilitya	Observed Absolute Riskb	Relative Risk (95% CI)c
Age, yr			0	Negligible	0.8% (0.2% to 1.6%)	<2%	0.05 (0.00 to 0.35)
<65	0.00	0	1
≥65	0.66	1	2
Diabetes mellitus			3
No	0.00	0
Yes	0.66	1	4	Low	6% (3% to 10%)	3%–14%	1.00
Preoperative eGFRd			5
60–69	3.16	5	6
70–79	2.41	4
80–89	1.76	3	7	Moderate	23% (17% to 29%)	21%–26%	2.71 (1.51 to 4.91)
≥90	0.00	0	8
Management plan
Partial nephrectomy	0.00	0	9	High	51% (43% to 59%)	46%–69%	5.93 (3.30 to 10.64)
Radical nephrectomy	1.79	3	10

Logistic coefficients are from model 3 (Table 1). To derive the points system, each coefficient was divided by the lowest value (0.66) and rounded to the nearest integer. 95% CI, 95% confidence interval.

^aMean (range) of predicted probability of the primary outcome for scores contained within respective strata.

^bRange of absolute risk of the outcome within each stratum across all four cohorts (excluding living kidney donor analysis).

^cRelative risk was calculated by comparing risk strata using a univariable log-binomial regression in the derivation cohort (with reference to the “low-risk” stratum).

^deGFR in ml/min per 1.73 m².