Table 2. Pairwise Comparisons Between GFR-Estimating Equations^a.

Pairwise Comparisons	Median (95% CI) Difference in Bias	P Values	Median (95% CI) Difference in P30	P Value
Whole Cohort (N = 2247)
CKD-EPI-LMR	−4.0 (−4.0 to −3.5)	<.001	−3.5 (−6.0 to −1.5)	<.001
CKD-EPI-FAS	−2.0 (−3.5 to −2.5)	<.001	−2.0 (−4.5 to 0.5)	.07
CKD-EPI-BIS 1	0.0 (−1.5 to 0.5)	.07	0.5 (0.0 to 0.5)	.48
Patients Aged 65-74 Years (N = 1710)
CKD-EPI-LMR	−4.0 (−4.5 to −3.5)	<.001	−4.0 (−3.5 to −1.5)	<.001
CKD-EPI-FAS	−2.0 (−2.5 to −1.0)	<.001	−2.0 (−3.5 to −1.5)	.002
CKD-EPI-BIS 1	−1.0 (−1.5 to −0.5)	.004	0.5 (0.0 to 0.5)	.66
Patients Aged ≥75 Years (N = 537)
CKD-EPI-LMR	−4.0 (−4.5 to −3.5)	<.001	−3.0 (−8.0 to 2.0)	.07
CKD-EPI-FAS	−3.0 (−3.5 to −2.5)	.001	−2.0 (−7.0 to 3.0)	.19
CKD-EPI-BIS 1	−1.0 (−1.5 to 0.5)	.46	1.0 (−0.5 to 0.5)	.68

Abbreviations: BIS 1, Berlin Initiative Study 1 equation; CKD-EPI, Chronic Kidney Disease Epidemiology Collaboration equation; FAS, full age spectrum equation; GFR, glomerular filtration rate; LMR, Lund-Malmö Revised equation.

^aMedian difference in bias is the difference between equation biases (measured GFR minus estimated GFR; a negative median difference means that, on average, the second equation provides closer values to measured GFR by inulin clearance than the first equation). P₃₀, percentage of estimates within 30% of the measured value; here too, a negative median difference means that, on average, more values from the second equation are close to measured GFR by inulin clearance than from the first equation). 95% CIs were calculated by a bootstrap method (2000 bootstraps) over all measure differences. The significance level was .005. 95% CI as calculated by a bootstrap method.