Ordering Recommendation

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Plasma separator tube or serum separator tube.

Specimen Preparation

Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.2 mL)

Storage/Transport Temperature


Unacceptable Conditions

Specimens obtained through catheters used to infuse hyperalimentation fluid. Specimens collected with potassium oxalate/sodium fluoride or sodium citrate.


Patient age and sex are required for calculation.


After separation from cells: Ambient: 1 week; Refrigerated: 1 week; Frozen: 3 months


Quantitative Enzymatic Assay




Within 24 hours

Reference Interval

Refer to Report

Calculated GFR - >= 60 mL/min / 1.73 square meters

Interpretive Data

The estimated glomerular filtration rate (eGFR) was calculated using the 2021 CKD-EPI eGFR creatinine equation, which does not include race as a factor. This equation is validated in individuals 18 years of age and older. Accurate estimation of GFR requires stable day-to-day creatinine. Creatinine-based eGFR is less accurate in patients with extremes of muscle mass, restriction of dietary protein, ingestion of creatine, extra-renal metabolism of creatinine, or treatment with medications that affect renal tubular creatinine secretion. The eGFR is normalized to a body surface area of 1.73 square meters.

GFR Categories in Chronic Kidney Disease (CKD)
GFR Category GFR (mL/min/1.73 square meters) Interpretation
G1 90 or greater Normal to high*
G2 60-89 Mild decrease*
G3a 45-59 Mild to moderate decrease
G3b 30-44 Moderate to severe decrease
G4 15-29 Severe decrease
G5 14 or less Kidney failure
*In the absence of evidence of kidney damage, neither GFR category G1 nor G2 fulfill the criteria for CKD (Kidney Int Suppl 2013;3:1-150)

Compliance Category



Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
0020025 Creatinine, Serum or Plasma 2160-0
3005479 EGFR, Calculated by CKD-EPI 2021 98979-8
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • cGFR
  • Calculated Glomerular Filtration Rate
  • eGFR
  • Estimated Glomerular Filtration Rate
Glomerular Filtration Rate (Estimated)