The diagnostic value of rescaled renal biomarkers serum creatinine and serum cystatin C and their relation with measured glomerular filtration rate.

•Rescaled renal biomarkers have a common normal reference interval of [0.67–1.33]•Subjects with rescaled renal biomarkers within the normal reference interval have normal glomerular filtration rate•the age-dependent threshold for GFR corresponds to the upper reference limit of 1.33 for the rescaled renal biomarkers•the fixed threshold for GFR of 60mL/min/1.73m2 results in a decreased specificity for children and a decreased sensitivity in older adults•impaired kidney function can be detected by the renal biomarkers without entering them in an eGFR equation