What is estimated GFR (eGFR)?

This article was first published on March 8, 2018. It was last reviewed, updated, or edited on December 18, 2023. The glomerular filtration rate (GFR) is the best clinically available index of kidney function. Why not measure GFR directly? Measuring the GFR is inconvenient because it requires a 24-hour collection of urine (which is hard…