description: 'Glomerular filtration rate (GFR) is considered the best overall index of kidney function; \nhowever measured GFR is not practical in the routine clinical setting. Estimated glomerular filtration \nrate (eGFR) is a suitable alternative and can be calculated for adults >= 18 years using an equation \nincorporating the patient''s age, gender, and measured serum/plasma/blood creatinine only (eGFRcr) (this term) \nor both serum/plasma/blood creatinine and serum/plasma cystatin-C (eGFRcr-cys) [LOINC: 98979-8](https://loinc.org/98979-8/).\nThe serum/plasma/blood creatinine value is based on a measurement procedure that is traceable to the isotope dilution\nmass spectrometry (IDMS) reference measurement procedure for creatinine. The 2021 CKD-EPI equations used for \neGFRcr and eGFRcr-cys do not have a race term as does the older estimating equations that they replace.\n[https://www.nejm.org/doi/pdf/10.1056/NEJMoa2102953](https://www.nejm.org/doi/pdf/10.1056/NEJMoa2102953)\n\nThere is a [corresponding calculator](https://www.kidney.org/professionals/gfr_calculator)\n\nFor children below 18 y there is a [Pediatric GFR Calculator](https://www.kidney.org/professionals/kdoqi/gfr_calculatorPed)'
package_name: ch.fhir.ig.ch-lab-report
derivation: constraint
name: ChLabObservation_eGFR_CKD_EPI_2021
type: Observation
elements:
  code:
    short: ValueSet for the allowed LOINC codes aiming at Creatinin / Creatinin and Cystatin C based eGFR
    binding: {strength: required, valueSet: 'http://fhir.ch/ig/ch-lab-report/ValueSet/observation-code-cdk-epi-2021'}
    index: 0
package_version: 2.0.0-ballot
class: profile
kind: resource
url: http://fhir.ch/ig/ch-lab-report/StructureDefinition/ch-lab-observation-egfr-ckd-epi-2021
base: http://fhir.ch/ig/ch-lab-report/StructureDefinition/ch-lab-observation-egfr
version: 2.0.0-ballot