Search

Background: A new cystatin C based European Kidney Function Consortium (EKFC CysC ) equation was recently developed for adults, using the same mathematical form as the previously published full age spectrum creatinine based EKFC-equation (EKFC Crea ). In the present study the cystatin C based EKFC-equation is extended to children, by defining the appropriate cystatin C rescaling factor Q CysC ., Methods: Rescaling factor Q CysC for cystatin C was defined as: a) 0.83 mg/L, exactly as it was defined for young adults in the adult equation, and b) a more complex Q CysC -age relationship based on 4 th degree cystatin C-age polynomials after evaluation of data from Uppsala, Stockholm and Canada and aggregated data from Germany. The EKFC CysC equation was then validated in an independent dataset in European children (n = 2,293) with measured GFR, creatinine, cystatin C, age, height and sex available., Results: The EKFC CysC with the simple Q CysC -value of 0.83 had a bias of -7.6 [95%CI -8.4;-6.5] mL/min/1.73 m 2 and a P30-value of 85.8% [95%CI 84.4;87.3] equal to the EKFC CysC with the more complex 4 th degree Q CysC -value. The arithmetic mean of the EKFC Crea and EKFC CysC with the simple Q CysC of 0.83 had a bias of -4.0 [95%CI -4.5;-3.1] mL/min/1.73 m 2 and P30 of 90.4% [95%CI 89.2;91.6] similar to using the more complex 4 th degree Q CysC -polynomial., Conclusion: Using exactly the same Q CysC of 0.83 mg/L, the adult EKFC CysC can easily be extended to children, with some bias but acceptable P30-values. The arithmetic mean of EKFC Crea and EKFC CysC results in bias closer to zero and P30 slightly over 90%., (© 2023. The Author(s), under exclusive licence to International Pediatric Nephrology Association.)

The main trends of indoor radon regulation in Europe are expressed through the standard ISO 11665-8. This standard, however, ignores the short-term tests (2-7 days in practice)-the main tests in the USA, and instead requires conducting long-term tests only (2-12 months)-without any justification. Moreover, the temporal (key) uncertainty of indoor radon is ignored altogether, a fact that does not allow the assessment of a room's conformity with a normative at a given reliability (usually 95%). Thus, the current international regulation is neither harmonised nor rational. This paper reports the interim results of storming discussions within the ISO 11665-8 Focus Group, in charge of revising the aforementioned standard. Proposed are the rational criterion for conformity assessment of a room with a normative for both short- and long-term measurements, as well as the indicative values and the algorithm for determining indoor radon temporal uncertainty depending on the measurement duration., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)