{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T10:29:21Z","timestamp":1787048961381,"version":"build-2736575974"},"reference-count":30,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T00:00:00Z","timestamp":1787011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Several updated equations based on creatinine and\/or cystatin C have been developed to estimate glomerular filtration rate (GFR), but their concordance in adolescents and young adults remains unclear. The CKiD Under 25 years (CKiDU25) equation was developed in children and young adults with chronic kidney disease, whereas the European Kidney Function Consortium (EKFC) equation was designed for use across the lifespan. Their agreement and the factors associated with eGFR category reclassification in healthy populations remain unexplored.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We compared the CKiDU25 and EKFC equations using combined estimates, defined as the mean of creatinine- and cystatin C-based eGFR for each equation, in adolescents and young adults from the National Health and Nutrition Examination Surveys 1999\u20132002. Factors associated with reclassification by the EKFC equation were examined.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The study included 4552 adolescents and young adults, representing a weighted population of approximately 57.26 million. The CKiDU25 equation showed an age-related decline in eGFR, particularly among Black males, whereas EKFC yielded more consistent eGFRs across demographic groups. Compared with CKiDU25, EKFC markedly reduced the estimated prevalence of reduced kidney function, defined as eGFR 60\u201389 mL\/min\/1.73 m2, in the healthy population (4.06% vs. 14.16%). Overall, 66.74% of participants were reclassified to a lower eGFR category by EKFC. Lower reclassification was more common among older participants, females, those without diabetes, and those with higher body mass index and waist-to-height ratio.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Equation selection substantially affects eGFR estimation and classification in healthy adolescents and young adults, underscoring the need to consider age, sex, and race when choosing GFR estimation equations.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/joneph\/aajag148","type":"journal-article","created":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T11:44:03Z","timestamp":1779882243000},"source":"Crossref","is-referenced-by-count":0,"title":["Low agreement among the equations in healthy children and young adults"],"prefix":"10.1093","author":[{"given":"Fan","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Pediatrics, West China Second University Hospital, Sichuan University , Section 3, Renmin South Road, Chengdu 610041 ,","place":["China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University , Chengdu 610041 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanjie","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, West China Second University Hospital, Sichuan University , Section 3, Renmin South Road, Chengdu 610041 ,","place":["China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University , Chengdu 610041 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuwei","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, West China Second University Hospital, Sichuan University , Section 3, Renmin South Road, Chengdu 610041 ,","place":["China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University , Chengdu 610041 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3089-2113","authenticated-orcid":false,"given":"Yong","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, West China Second University Hospital, Sichuan University , Section 3, Renmin South Road, Chengdu 610041 ,","place":["China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University , Chengdu 610041 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,8,18]]},"reference":[{"key":"2026081806055420800_aajag148-B1","doi-asserted-by":"publisher","first-page":"177","DOI":"10.1038\/s41581-018-0080-9","article-title":"Estimated GFR: time for a critical appraisal","volume":"15","author":"Porrini","year":"2019","journal-title":"Nat Rev Nephrol."},{"key":"2026081806055420800_aajag148-B2","doi-asserted-by":"publisher","first-page":"S1","DOI":"10.1016\/j.kint.2021.05.021","article-title":"KDIGO 2021 clinical practice guideline for the management of glomerular diseases","volume":"100","author":"Rovin","year":"2021","journal-title":"Kidney Int."},{"key":"2026081806055420800_aajag148-B3","doi-asserted-by":"publisher","first-page":"31","DOI":"10.1159\/000180580","article-title":"Prediction of creatinine clearance from serum creatinine","volume":"16","author":"Cockcroft","year":"1976","journal-title":"Nephron"},{"key":"2026081806055420800_aajag148-B4","doi-asserted-by":"publisher","first-page":"629","DOI":"10.1681\/ASN.2008030287","article-title":"New equations to estimate GFR in children with CKD","volume":"20","author":"Schwartz","year":"2009","journal-title":"J Am Soc Nephrol."},{"key":"2026081806055420800_aajag148-B5","doi-asserted-by":"publisher","first-page":"51","DOI":"10.1038\/s41581-019-0191-y","article-title":"Measured and estimated glomerular filtration rate: current status and future directions","volume":"16","author":"Levey","year":"2020","journal-title":"Nat Rev Nephrol."},{"key":"2026081806055420800_aajag148-B6","doi-asserted-by":"publisher","first-page":"445","DOI":"10.1038\/ki.2012.169","article-title":"Improved equations estimating GFR in children with chronic kidney disease using an immunonephelometric determination of cystatin C","volume":"82","author":"Schwartz","year":"2012","journal-title":"Kidney Int."},{"key":"2026081806055420800_aajag148-B7","doi-asserted-by":"publisher","first-page":"39","DOI":"10.1258\/acb.2012.011241","article-title":"The relative effects of fat versus muscle mass on cystatin C and estimates of renal function in healthy young men","volume":"50","author":"Chew-Harris","year":"2013","journal-title":"Ann Clin Biochem."},{"key":"2026081806055420800_aajag148-B8","doi-asserted-by":"publisher","first-page":"583","DOI":"10.1001\/jamapediatrics.2015.54","article-title":"Association of definition of acute kidney injury by cystatin C rise with biomarkers and clinical outcomes in children undergoing cardiac surgery","volume":"169","author":"Zappitelli","year":"2015","journal-title":"JAMA Pediatr."},{"key":"2026081806055420800_aajag148-B9","doi-asserted-by":"publisher","first-page":"194","DOI":"10.1186\/s12882-018-0995-1","article-title":"Low agreement between modified-Schwartz and CKD-EPI eGFR in young adults: a retrospective longitudinal cohort study","volume":"19","author":"Webster-Clark","year":"2018","journal-title":"BMC Nephrol."},{"key":"2026081806055420800_aajag148-B10","doi-asserted-by":"publisher","first-page":"604","DOI":"10.7326\/0003-4819-150-9-200905050-00006","article-title":"Chronic kidney dis epidemiology, c.a new equation to estimate glomerular filtration rate","volume":"150","author":"Levey","year":"2009","journal-title":"Ann Intern Med."},{"key":"2026081806055420800_aajag148-B11","doi-asserted-by":"publisher","first-page":"1234","DOI":"10.1016\/j.kint.2018.12.020","article-title":"Estimating glomerular filtration rate at the transition from pediatric to adult care","volume":"95","author":"Pottel","year":"2019","journal-title":"Kidney Int."},{"key":"2026081806055420800_aajag148-B12","doi-asserted-by":"publisher","first-page":"948","DOI":"10.1016\/j.kint.2020.10.047","article-title":"Age- and sex-dependent clinical equations to estimate glomerular filtration rates in children and young adults with chronic kidney disease","volume":"99","author":"Pierce","year":"2021","journal-title":"Kidney Int."},{"key":"2026081806055420800_aajag148-B13","doi-asserted-by":"publisher","first-page":"2213","DOI":"10.1007\/s00467-022-05429-0","article-title":"Evaluation of the creatinine-based chronic kidney disease in children (under 25 years) equation in healthy children and adolescents","volume":"37","author":"Pottel","year":"2022","journal-title":"Pediatr Nephrol"},{"key":"2026081806055420800_aajag148-B14","doi-asserted-by":"publisher","first-page":"333","DOI":"10.1056\/NEJMoa2203769","article-title":"Cystatin C-based equation to\u00a0estimate gfr without the inclusion of race and sex","volume":"388","author":"Pottel","year":"2023","journal-title":"N Engl J\u00a0Med."},{"key":"2026081806055420800_aajag148-B15","author":"CDC"},{"key":"2026081806055420800_aajag148-B16","doi-asserted-by":"publisher","first-page":"272","DOI":"10.1001\/jamapediatrics.2014.3216","article-title":"Prevalence of and trends in dyslipidemia and blood pressure among US children and adolescents, 1999-2012","volume":"169","author":"Kit","year":"2015","journal-title":"JAMA Pediatr."},{"key":"2026081806055420800_aajag148-B17","author":"Institute., C. a. L. S"},{"key":"2026081806055420800_aajag148-B18","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1016\/S0140-6736(86)90837-8","article-title":"Statistical methods for assessing agreement between two methods of clinical measurement","volume":"1","author":"Bland","year":"1986","journal-title":"Lancet"},{"key":"2026081806055420800_aajag148-B19","doi-asserted-by":"publisher","first-page":"276","DOI":"10.11613\/BM.2012.031","article-title":"Interrater reliability: the kappa statistic","volume":"22","author":"McHugh","year":"2012","journal-title":"Biochem Med (Zagreb)."},{"key":"2026081806055420800_aajag148-B20","doi-asserted-by":"publisher","first-page":"965","DOI":"10.1093\/jssam\/smz036","article-title":"Multiple imputation with survey weights: a multilevel approach","volume":"8","author":"Quartagno","year":"2020","journal-title":"J Surv Stat Methodol."},{"key":"2026081806055420800_aajag148-B21","doi-asserted-by":"publisher","first-page":"2409","DOI":"10.1002\/sim.1047","article-title":"A solution to the problem of separation in logistic regression","volume":"21","author":"Heinze","year":"2002","journal-title":"Stat Med."},{"key":"2026081806055420800_aajag148-B22","doi-asserted-by":"publisher","first-page":"1169","DOI":"10.1007\/s00467-023-06185-5","article-title":"Limitations of U25 CKiD and CKD-EPI eGFR formulae in patients 2-20 years of age with measured GFR &gt; 60 mL\/min\/1.73 m2-a cross-sectional study","volume":"39","author":"Filler","year":"2024","journal-title":"Pediatr Nephrol"},{"key":"2026081806055420800_aajag148-B23","doi-asserted-by":"publisher","first-page":"229","DOI":"10.1152\/jappl.1997.83.1.229","article-title":"Appendicular skeletal muscle mass: effects of age, gender, and ethnicity","volume":"83","author":"Gallagher","year":"1997","journal-title":"J Appl Physiol (1985)"},{"key":"2026081806055420800_aajag148-B24","doi-asserted-by":"publisher","first-page":"992","DOI":"10.2215\/CJN.00090108","article-title":"Higher serum creatinine concentrations in black patients with chronic kidney disease: beyond nutritional status and body composition","volume":"3","author":"Hsu","year":"2008","journal-title":"Clin J Am Soc Nephrol."},{"key":"2026081806055420800_aajag148-B25","doi-asserted-by":"publisher","first-page":"635","DOI":"10.1007\/s40620-014-0077-9","article-title":"A longitudinal assessment of the natural rate of decline in renal function with age","volume":"27","author":"Cohen","year":"2014","journal-title":"J Nephrol."},{"key":"2026081806055420800_aajag148-B26","doi-asserted-by":"publisher","first-page":"153","DOI":"10.1016\/j.exger.2016.03.013","article-title":"Kidney and aging - A narrative review","volume":"87","author":"Gekle","year":"2017","journal-title":"Exp Gerontol."},{"key":"2026081806055420800_aajag148-B27","doi-asserted-by":"publisher","first-page":"105","DOI":"10.1159\/000450893","article-title":"Glomerular filtration rate in healthy living potential kidney donors: a meta-analysis supporting the construction of the full age spectrum equation","volume":"135","author":"Pottel","year":"2017","journal-title":"Nephron"},{"key":"2026081806055420800_aajag148-B28","doi-asserted-by":"publisher","first-page":"497","DOI":"10.1093\/ndt\/gfw425","article-title":"Estimating glomerular filtration rate for the full age spectrum from serum creatinine and cystatin C","volume":"32","author":"Pottel","year":"2017","journal-title":"Nephrol Dial Transplant"},{"key":"2026081806055420800_aajag148-B29","doi-asserted-by":"publisher","first-page":"20","DOI":"10.1056\/NEJMoa1114248","article-title":"Estimating glomerular filtration rate from serum creatinine and cystatin C","volume":"367","author":"Inker","year":"2012","journal-title":"N Engl J Med."},{"key":"2026081806055420800_aajag148-B30","doi-asserted-by":"publisher","first-page":"2258","DOI":"10.1093\/ckj\/sfac182","article-title":"Standardization of serum creatinine is essential for accurate use of unbiased estimated GFR equations: evidence from three cohorts matched on renal function","volume":"15","author":"Pottel","year":"2022","journal-title":"Clin Kidney J."}],"container-title":["Journal of Nephrology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/joneph\/advance-article-pdf\/doi\/10.1093\/joneph\/aajag148\/70679149\/aajag148.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/joneph\/advance-article-pdf\/doi\/10.1093\/joneph\/aajag148\/70679149\/aajag148.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T10:05:58Z","timestamp":1787047558000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/joneph\/advance-article\/doi\/10.1093\/joneph\/aajag148\/8763264"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,18]]},"references-count":30,"URL":"https:\/\/doi.org\/10.1093\/joneph\/aajag148","relation":{},"ISSN":["1121-8428","1724-6059"],"issn-type":[{"value":"1121-8428","type":"print"},{"value":"1724-6059","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,18]]},"article-number":"aajag148"}}