I have learned the unit of glomerular filtration rate (GFR) is commonly reported in mL/min/1.73m².

I cannot figure out the 1.73, is it just a scaling factor to get a number around 100 or does it have medical relevance?

1 Answer 1


From the National Kidney Foundation:

Kidney function is proportional to kidney size, which is proportional to body surface area (BSA). Adjustment for BSA is necessary when comparing a person’s GFR to normal values, to the GFR criterion for the diagnosis of CKD, and to levels defining the stages of CKD. A BSA of 1.73 m2 was the normal mean value for young adults when indexing was proposed.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.